Chem Lab final 5-10

23: A 50mL volumetric flask is calibrated to the _______ and will hold exactly _________ when filled to the calibration line: 0.01mL, 100.00mL 0.01mL, 50.00mL 0.01mL. 50.000mL 0.01mL, 50.0mL 0.1mL, 50.00mL 0.1mL, 50.0mL 0.1mL, 50mL

0.01mL, 50.00mL

26: A 50mL volumetric flask is calibrated to the _______ and will hold exactly _________ when filled to the calibration line: 0.01mL, 100.00mL 0.01mL, 50.00mL Rationale: Please refer to Appendix III in your Lab Manual. 0.01mL. 50.000mL 0.01mL, 50.0mL 0.1mL, 50.00mL 0.1mL, 50.0mL 0.1mL, 50mL

0.01mL, 50.00mL

18: Gloves worn in the chemistry lab must be latex-free. TRUE FALSE

TRUE

10: You have taken more acid than you need for your experiment. What is the proper step to take? You pour the acid back into the reagent bottle so as not to waste it. You pour the extra down the drain. You dispose of the extra chemical in the specified container and pour more carefully next time. You share the acid with another lab group so as not to waste it.

You dispose of the extra chemical in the specified container and pour more carefully next time.

31: Describe the following analysis as either quantitative, qualitative, or both: A 100.0mL solution contains a blue suspension Qualitative Quantitative Both

both

19: An analysis of generic antacid tablets labeled to contain 750mg of CaCO3 (MM= 100.09g/mol) per tablet of active ingredient was performed. The analysis was performed by dissolving a 0.985g sample of the antacid tablet in 90.00mL of 0.175M HCl. The excess acid was back-titrated with exactly 33.15mL of 0.155M NaOH. The average weight of a tablet is 1.025g. The tablet came from a bottle of 175 tablets that cost $4.99. Calculate the moles of HCl neutralized by 1.00g of the antacid tablet. 1.10x10-2 mol 1.58x10-2mol 1.06x10-2 mol 2.09x10-2 mol 5.14x10-3 mol 1.08x10-2 mol

1.08x10-2 mol

27: Which of the following serves as the indicator for the titration? Vitamin C 2,6-dichloroindophenol Ascorbic acid Metaphosphoric acid

2,6-dichloroindophenol

27: Place the following steps for lighting a Bunsen burner in their correct order: A striker positioned above the burner can be used to ignite the gas. Check that the gas valve is open on the Bunsen buner. Make sure that the connections are secure at both the gas outlet and at the burner. The tip of the inner core of the flame should be at the base of the glassware. Turn on the gas outlet and listen for the flow of gas. Adjust the gas valve and the air flow regulator on the burner until the flame is about two inches in height. 1,2,3,4,5,6 3,2,5,1,6,4 6,5,4,3,2,1 3,2,5,6,4,1

3,2,5,1,6,4

29: How much heat is absorbed by a 115g sample of water when it is heated from 25.200C to 32.800C? The specific heat of water is 4.184 J/g0C. 3.66x103 kJ 3.66 kJ 1.58x104 kJ 15.8 kJ 1.21x104 kJ 12.1 kJ

3.66 kJ

29: One possible method for the determination of glucose concentration is based on the formation of a blue-green complex of glucose with o-toluidine in glacial acetic acid. The reaction is as follows: HOCH2(CHOH)4CHO(glucose) + H2N(C6H4)CH3 (o-toluidine)↔ HOCH2(CHOH)4CH=N(C6H4)CH3(blue-green complex) + H2O A stock solution was prepared by dissolving and diluting 0.725g of glucose (MM=180.156g/mol) to 100.00mL with deionized water. What is the concentration of the stock solution? 1.31x104M 4.02x10-1M 1.31x103M 1.31 M 2.49 M 1.31x101M 2.48x101M 2.48x104M 4.02x10-2M 4.02x10-5M 2.49x103M 4.02x10-4M None of the above

4.02x10-2M

29: An analysis of generic antacid tablets labeled to contain 550mg of CaCO3 (MM= 100.09g/mol) per tablet of active ingredient was performed. The analysis was performed by dissolving a 0.850g sample of the antacid tablet in 70.00mL of 0.0957M HCl. The excess acid was back-titrated with exactly 13.46mL of 0.1305M NaOH. The average weight of a tablet is 1.550g. The tablet came from a bottle of 125 tablets that cost $2.79. Calculate the cost effectiveness of the antacid. 0.221 mol/¢ 2.21x10-3 mol/¢ 0.261 mol/¢ 2.61x10-3 mol/¢ 0.443 mol/¢ 4.43x10-3 mol/¢ .111 mol/¢ 1.11x10-3 mol/¢ 0.404 mol/¢ 4.04x10-3 mol/¢

4.04x10-3 mol/¢

2: An analysis of generic antacid tablets labeled to contain 550mg of CaCO3(MM= 100.09g/mol) per tablet of active ingredient was performed. The analysis was performed by dissolving a 0.850g sample of the antacid tablet in 70.00mL of 0.0957M HCl. The excess acid was back-titrated with exactly 13.46mL of 0.1305M NaOH. The average weight of a tablet is 1.550g. The tablet came from a bottle of 125 tablets that cost $2.79. Calculate the moles of HCl neutralized by the tablet. 9.01x10-3 mol 6.70x10-3 mol 8.46x10-3 mol 4.94x10-3 mol 1.76x10-3 mol 5.82x10-3 mol

9.01x10-3 mol

8: What is a state function? The study of heat flow. A process that releases heat to the surroundings. A quantity dependent only on its current state but not how it got there. The measurement of the amount of heat absorbed by a calorimeter. A change in temperature.

A quantity dependent only on its current state but not how it got there.

5: What are the advantages to using back titration to analyze an antacid? Check all that apply. Back titration will allow us to perform a strong acid/strong base titration. The base of the antacid will be completely neutralized. We will not have to heat the solution. Strong Acid/Strong Base titrations are simpler to analyze than strong acid/weak base titrations. (correct)

Back titration will allow us to perform a strong acid/strong base titration. The base of the antacid will be completely neutralized.

26: Why are we cautious in the handling of acids and bases, no matter what their concentration? We only need to be cautious handling acids and bases of relatively high concentrations. Because acids and bases can react violently at any concentration.

Because acids and bases can react violently at any concentration.

27: Describe the following analysis as either quantitative, qualitative, or both: A green solid has a mass of 3.74kg Qualitative Quantitative Both

Both

35: What hazards are associated with the iron(III) nitrate being used in the Qualitative Analysis Experiment? Check all that apply. Toxic Corrosive Irritant to skin Irritant to respiratory tract Causes skin discoloration Oxidant Carcinogen

Corrosive (correct) Irritant to skin (correct) Irritant to respiratory tract (correct) Oxidant (correct)

8: What hazards are associated with the 0.6M HCl being used in the Back Titration experiment? Check all that apply. Corrosive Irritant to skin Irritant to eyes Carcinogen Toxic

Corrosive, irritant to skin, irritant to eyes, toxic

24: The students working at lab bench F13 on the 20th of March want to save their second graph, under what file name should they save it? F_3/20_2 F13_3/20_1.2 F13_3-20_2 13_3-20_2 F13_3/20_2

F13_3-20_2

39: What hazards are associated with the bromophenol blue being used in the Back Titration experiment? Check all that apply. Corrosive Toxic Oxidizer Irritant to skin (correct) Irritant to eyes (correct) Carcinogen Hygroscopic

Irritant to skin & irritant to eyes

36: Why are we cautious in the handling of acids and bases, no matter what their concentration? We don't have to be cautious if the acids and bases are very dilute, only if they're very concentrated. We have to be cautious? Acids and bases are always really dangerous No matter their concentration, acids and bases can be corrosive, toxic and irritating.

No matter their concentration, acids and bases can be corrosive, toxic and irritating.

20: The following data was collected by a student performing the DETERMINING THE MOLAR ENTHALPY OF NEUTRALIZATION portion of the experiment. 50.00mL of a 0.250M acid is combined with 50.00mL of 0.255M NaOH. Before the reaction, the acid and base are at a temperature of 24.92°C. After mixing, the neutralized solution reaches a maximum temperature of 26.50°C in a calorimeter (Ccal=58.4J/°C). The neutralized solution has a specific heat of 3.89 J/g°C and a density of 1.04g/mL. What is the molar enthalpy of neutralization in kJ/mol? 639 kJ/mol 639 kJ/mol -3.30x104 kJ/mol -33.0 kJ/mol -3.30x107 kJ/mol -731 kJ/mol -0.731 kJ/mol -7.31x105 kJ/mol -5.85x104 kJ/mol -58.5 kJ/mol -5.85x107 kJ/mol -5.74x107 kJ/mol -57.4 kJ/mol -5.74x104 kJ/mol -412 kJ/mol -4.12x105 kJ/mol -0.412 kJ/mol

-58.5 kJ/mol

15: Which of the following is NOT proper attire for the lab (check all that apply): Sweat pants Tights Closed-toe shoes which leave the top of the foot exposed Long sleeved shirt with close-fitting sleeves Long hair that has been pinned back

Tights & closed-toe shoes which leave the top of the foot exposed

20: What concentration sodium hydroxide will we be using in the Intro to Lab Quest © Experiment? 2.0M 1.0M 0.2M 0.1M 0.02M 0.01M None of the above, we aren't using NaOH

0.2M

25: An analysis of generic antacid tablets labeled to contain 750mg of CaCO3 (MM= 100.09g/mol) per tablet of active ingredient was performed. The analysis was performed by dissolving a 0.985g sample of the antacid tablet in 90.00mL of 0.175M HCl. The excess acid was back-titrated with exactly 33.15mL of 0.155M NaOH. The average weight of a tablet is 1.025g. The tablet came from a bottle of 175 tablets that cost $4.99. Calculate the mass effectiveness of the antacid. 92.8 mol/g 89.2 mol/g 91.4 mol/g 186 mol/g 193 mol/g 95.1 mol/g 96.6 mol/g 1.05x10-2 mol/g 1.08x10-2 mol/g 1.12x10-3 mol/g 1.09x10-2 mol/g 5.39x10-3 mol/g 1.04x10-2 mol/g 5.18x10-3 mol/g

1.08x10-2 mol/g

37: What is leuco dye? A coloring agent in orange juice A DCP reduction product A DCP oxidation product An additive used in vitamin C analysis to denature and precipitate proteins And additive used to prevent the decomposition of vitamin C

A DCP reduction product

14: The following equation: 2Al+3(aq) + 3SO4-2(aq) + 6Na+(aq) + 6OH-(aq)→ 2Al(OH)3(s) + 6Na+(aq) ) + 3SO4-2(aq) Is an example of: A net ionic equation A complete ionic equation A molecular equation A complexation equation

A complete ionic equation

35: Eye Protection: Students are required to bring goggles. Goggles must be approved and full splash-proof All of the above

All of the above

2: What plays the role of the oxidizing agent in our reaction? Ascorbic acid DCP Metaphosphoric acid pH 3 buffer the indicator

DCP

27: Which of the following is not considered volumetric glassware? Erlenmeyer flasks Volumetric flasks Burets Pipets

Erlenmeyer flasks

32: Which of the following is not considered volumetric glassware? Erlenmeyer flasks Volumetric flasks Burets Pipets

Erlenmeyer flasks

25: Why is wearing eye protection (full splash-proof goggles) at all times in this laboratory a requirement? Because the instructors think you look funny with them on. To protect your eyes from damage!

To protect your eyes from damage!

13: What hazards are associated with the Sodium Hydroxide being used in the Qualitative Analysis Experiment? Check all that apply. Toxic Corrosive Irritant to skin Irritant to respiratory tract Causes skin discoloration Carcinogen

Toxic (correct) Corrosive (correct) Irritant to skin (correct) Irritant to respiratory tract (correct)

16: What hazards are associated with the sodium hydroxide being used in the Intro to Lab Quest © Experiment? Toxic Corrosive Irritant to respiratory tract Carcinogen a and b a, b, and c a, b, and d all of the above

a,b,c

17: All glassware should be labeled with the name and concentration of the chemical that it contains. TRUE FALSE

true

14: A student used a DCP solution (standardized to 9.98x10-4M) to analyze a sample of extract from 2.50g of solid food. The titration required 22.49mL of DCP. 87.00% of all the ascorbic acid in the food was collected in the extract. (MM Ascorbic Acid = 176.124 g/mol) What mass of food (in grams) would be required to attain the RDA of ascorbic acid (60 mg) 33.0 g 3.30x10-2 g 3.30 g 21.8 g 2.18 g 2.18x103 g 45.4 g 4.54 g 4.54x10-3 g 182 g 0.182 g 1.82 x10-3 g 39.5 g 3.95 g 3.95x10-3 g

33.0 g

12: How many graphs will you turn in at the end of the experiment? We aren't turning in any graphs! 1 2 3 4 5 6 7 8 9 None of the above

8

4: What is true about a meniscus? A meniscus is the curvature of the upper surface of a liquid in glassware due to tension forces acting between the glass and the liquid. Rationale: Incorrect Note: Please refer to Appendix III of your lab manual. A meniscus for aqueous solutions is always convex. We always read the bottom of a meniscus. All of the above.

A meniscus is the curvature of the upper surface of a liquid in glassware due to tension forces acting between the glass and the liquid.

6: What hazards are associated with the 1.0M NaOH being used in the Back Titration experiment? Check all that apply. Corrosive Toxic Oxidizer Carcinogen Hygroscopic

Corrosive & toxic

8: Which species is reduced in our reaction? Ascorbic acid DCP Metaphosphoric acid pH 3 buffer the indicator

DCP

16: In which parts of the experiment will we be using a hot plate? Check all that apply." Determining the Calorimeter Constant Determine the Specific Heat and Molar Heat Capacity of Copper Determining the Molar Enthalpy of Solution of an Aqueous Ionic Salt Determining the Molar Enthalpy of Neutralization

Determining the Calorimeter Constant (correct) Determine the Specific Heat and Molar Heat Capacity of Copper (correct)

13: Accuracy is a measure of: Precision. How close the measurement is the actual measurement. Rationale: Please refer to Appendix I of your lab manual. The quality of the work the lab technician is doing. The quality of the instrument used to do the measurement.

How close the measurement is the actual measurement.

41: Which scientist who studied the effects of vitamin C won two Nobel Prizes? Charles G. King Hoffman-La Roche James Lind Linus Pauling Szent-Gyorgyi

Linus Pauling (correct)

39: Which parts of the experiment require an analytical balance? Select all that apply. Part I- Standardizing the DCP solution Part II- Analyzing Juices for Vitamin C Content Part III- Analyzing a Vitamin Supplement for Vitamin C content (correct)

Part I- Standardizing the DCP solution

15: In this experiment, you will employ the ammonia, NH3, and the thiocyanate ion, SCN-, for much the same purpose. The common purpose is: To form a complex. As an acid As an acid-base indicator as a metal cation.

To form a complex

21: What hazards are associated with the potassium thiocyanate being used in the Qualitative Analysis Experiment? Check all that apply. Toxic Corrosive Irritant to skin Irritant to respiratory tract Causes skin discoloration Carcinogen

Toxic Irritant to skin Irritant to respiratory tract

10: What do we mean by "waste minimization?" We try to use as little reagents as possible during the experiment. We take only the amounts of reagents necessary to complete the experiment. We dispose of waste in proper containers. We do not return excess waste to the reagent bottles. All of the above

All of the above

40: Which species is oxidized in our reaction? Ascorbic acid DCP Metaphosphoric acid pH 3 buffer the indicator

Ascorbic acid

36: You do not know where to properly discard something. Uh oh! What should you do? Ask your instructor so that it gets disposed of properly. Take your best guess.

Ask your instructor so that it gets disposed of properly.

19: Why do reagents like NaOH and DCP need to be standardized before use? Because they degrade over time and as a result, the concentration decreases. Because they are used as standards. Because they degrade over time and as a result, the concentration increases. Because they react over time and as a result, the concentration increases. NaOH and DCP do not need to be standardized.

Because they degrade over time and as a result, the concentration decreases.

13: A small amount of chemical has spilled on your skin. What do you do? Leave the lab immediately and go to the student health center. Head for the eyewash station. Wash off affected area with cold water for at least 15 minutes. Immediately notify your lab instructor. Both c and d.

Both c and d

14: Your cell-phone is permitted in lab. TRUE FALSE

False

28: Gum chewing is permitted in the lab: TRUE FALSE

False

4: Gloves can be disposed of in the regular trash TRUE FALSE

False

7: Which one of the following strong acids will we react with an antacid tablet in this experiment? HNO3(aq) HCl(aq) H2SO4(aq) H2CO3(aq)

HCl(aq)

30: Broken Glass, Disposable Pipets, and gloves are all discarded: In the regular trash. In special, labeled, thick-walled containers that are located throughout the lab In the liquid hazardous waste drum. Outside of the lab.

In special, labeled, thick-walled containers that are located throughout the lab

4: What role does the metaphosphoric acid play in the vitamin C analysis? It precipitates proteins present in foods It prevents side reactions with sulfhydryl compounds and phenols It prevents the decomposition of vitamin c All of the above a and b a and c b and c

It precipitates proteins present in foods

18: In a graduated cylinder, what part of the meniscus should be used to indicate the volume? Always measure at the bottom of the curve of the meniscus Measure at the part of the meniscus closest to the glass wall Measure either the top of the meniscus if the liquid forms a convex surface, or the bottom of the meniscus if the liquid forms a concave surface. Always measure at the top of the curve of the meniscus.

Measure either the top of the meniscus if the liquid forms a convex surface, or the bottom of the meniscus if the liquid forms a concave surface.

3: Explain the term parallax in the context of reading a meniscus and how you would avoid any error that might be introduced by parallax? Parallax error is the apparent displacement of an object as seen from two different viewpoints that are not in line with the object. The meniscus must consistently be read at eye level. Parallax provides the depth perception necessary for our measurement. The meniscus must be read consistently at arm's length. Parallax error is the apparent displacement of an object as seen from two different viewpoints that are not in line with the object. The meniscus must be consistently be read from the top of the graduated cylinder. Parallax provides the depth perception necessary for our measurement. The meniscus must be read consistently from the top of the graduated cylinder.

Parallax error is the apparent displacement of an object as seen from two different viewpoints that are not in line with the object. The meniscus must consistently be read at eye level.

7: Describe the following analysis as either quantitative, qualitative, or both: Mixing solutions X (clear) and Z (red) makes a violet solution Qualitative Quantitative Both

Qualitative

19: Describe the following analysis as either quantitative, qualitative, or both: A solution has a pH of 6.24 Qualitative Quantitative Both

Quantitative

1: A scientist does two sets of experiments with three trials each to determine the density of an unknown solution. The three trials for the first experiment have a standard deviation of 0.0980g/mL. The three trials for the second experiment have a standard deviation of 0.0137g/mL. What can we infer? The measurements from the first experiment were more accurate. The measurements from the first experiment were more precise. The measurements from the second experiment were more accurate. The measurements from the second experiment were more precise. Rationale: Please refer to Appendix I in your lab manual. a and b a and d c and d All of the above None of the above.

The measurements from the second experiment were more precise.

9: Suppose that you run a chemical reaction in a constant-pressure calorimeter and you observe the temperature of the contents of the calorimeter decrease. What is the most likely reason? Gaseous products are formed. The calorimeter leaked heat. The reaction is exothermic. The reaction is endothermic.

The reaction is endothermic.

28: Which of the following is NOT proper attire for the lab (check all that apply): Sweat pants Tights Closed-toe shoes which leave the top of the foot exposed Long sleeved shirt with close-fitting sleeves Long hair that has been pinned back

Tights (correct) Closed-toe shoes which leave the top of the foot exposed (correct)

24: What hazards are associated with the copper(II) nitrate being used in the Qualitative Analysis Experiment? Check all that apply. Toxic Oxidant Irritant to skin Irritant to respiratory tract Causes skin discoloration Corrosive Carcinogen

Toxic (correct) Oxidant (correct) Irritant to skin (correct) Irritant to respiratory tract (correct)

34: You find a beaker filled with an unknown clear liquid on your lab bench. What should you do? Pour the liquid down the sink, it's probably water. Taste or smell the liquid to see if it's acidic or basic. Treat the liquid as hazardous; inform your instructor so that you can be notified of the proper disposal technique. Pour the contents into the liquid hazardous waste container. Try combining it with another chemical... maybe the subsequent reaction will help you identify it!

Treat the liquid as hazardous; inform your instructor so that you can be notified of the proper disposal technique.

29: You must prepare your data sheets for the lab for Parts I-IV (see sample on page 83 of your manual). Be sure to include Reagents, amount, concentration, and associated cautions for each Part. Observations and results will be filled in as you complete your experiment. Each person must complete a set of data sheets. Your data sheets will be graded by your instructor when you enter the laboratory. If a data sheet is typed: Your name, lab bench, and the date must be TYPED on each data sheet, not handwritten. Alternatively, you can hand-write the entire set of data sheets. You will complete your data sheets and turn them in to your instructor when you enter lab: TRUE FALSE

True

33: If an instructor asks you what is in a beaker, you will be able to tell them the identity and concentration of the chemical in the beaker. TRUE FALSE

True

34: If an instructor asks you what is in a beaker, you will be able to tell them the identity and concentration of the chemical in the beaker. TRUE FALSE

True

23: What's the best way to collect chemical waste as you do your experiment? Make several trips to the white drum to dispose of liquid waste from each beaker individually. Use your largest beaker as a labeled "WASTE" beaker, unless your instructor specifies otherwise, and then empty that beaker into the white drum. Use a waste beaker, but fill it to the brim before dumping it in the white drum, saving yourself extra trip!

Use your largest beaker as a labeled "WASTE" beaker, unless your instructor specifies otherwise, and then empty that beaker into the white drum.

7: The correct procedure for transferring liquid with a volumetric pipet. 1. First clean and rinse your pipet with tap water and do a second rinse with deionized water. 2.If using an atomizer bulb: Compress the rubber bulb and place it carefully over the upper end of the pipet. The bulb only needs to cover the end of the pipet to create an airtight seal, there is no need to push the pipet farther into the bulb. You may want to lubricate the hole of the rubber bulb with a drop of deionized water. If using a rolling pipet top: Press the proper sized pipet top tightly onto the end of the pipet in order to create an airtight seal. 3.Place the tip of the pipet in the liquid and draw the liquid into the pipet and above the calibration line. Keep the pipet tip submerged to avoid air bubble entry. Be careful not to draw the liquid into the bulb. Dispose of this first amount of liquid into a waste beaker. 4.Once again, draw in the liquid to be measured above the calibration line in the pipet. If using an atomizer bulb: remove the bulb while simultaneously covering the tip of the pipet with your finger. Now allow the liquid level to drop to the required level by slowly allowing air to enter the pipet by a controlled lifting of the finger that is covering the end of the pipet. If using a rolling pipet top, there is no need to remove the top. Push the side button to allow your pipet to drain. 5.When the liquid level is at the correct place, move the pipet tip to the glassware where you want the liquid delivered and release your finger. Allow the pipet to drain into the container and touch off any last drop on the pipet side of the glassware. 6.There may be some liquid remaining in the pipet tip. Do no blow this remaining liquid from the pipet. The pipet was calibrated to deliver the correct volume with this liquid remaining. 7.NEVER allow the liquid to enter the pipet top (atomizer bulb or rolling). What would you do if there was a tiny bit of liquid left inside the end of the pipet after the pipet has drained: You should blow through the pipet to drain this last drop so that your transfer will be accurate. You should touch any hanging drop of solution to the side of your beaker, but leave the small amount within the pipet. You should use a graduated cylinder instead, they're more precise than a volumetric pipet.

You should touch any hanging drop of solution to the side of your beaker, but leave the small amount within the pipet.

25: Systematic error occurs when An instrument is consistently yielding a high or low value for a result. A lab technician is erroneously making the same measuring mistake. A system failure occurs in computer analysis a & b Rationale: Incorrect Note: Please refer to Appendix I of your lab manual.

a&b

21: What are the goals of this experiment? To connect the probes to the LabQuest� interface To login to the laboratory computer network To locate and start the LoggerPro� program To measure the temperature and/or pH of various solutions and conduct a titration Explore the graphing and analysis capabilities of LoggerPro� A, b, c, and e All of the above

all of the above

11: In error analysis, precision and accuracy are a measure of the same experimental phenomenon. TRUE FALSE

false

23: Your cell-phone is permitted in lab. TRUE FALSE

false

25: One possible method for the determination of glucose concentration is based on the formation of a blue-green complex of glucose with o-toluidine in glacial acetic acid. The reaction is as follows: HOCH2(CHOH)4CHO(glucose) + H2N(C6H4)CH3 (o-toluidine)↔ HOCH2(CHOH)4CH=N(C6H4)CH3(blue-green complex) + H2O A stock solution was prepared by dissolving and diluting 0.668g of glucose (MM=180.156g/mol) to 100.00mL with deionized water. A dilution was prepared from the stock solution by treating 15.00mL of the stock solution with o-toluidine and diluting to 100.00mL with deionized water. Colorimetric determination gave that the transmittance of the sample was 50.3% when the path length of the light through the solution was exactly 1cm. Calculate the Absorbance for the species. 0.298 0.0170 3.18 2.30 1.92 0.230 1.70 2.69 0.170 None of the above because the units are missing None of the above because the values are wrong j & k

0.298

6: What concentration of hydrochloric acid will we be using in the Intro to Lab Quest© Experiment? 2.0M 1.0M 0.2M 0.1M 0.02M 0.01M None of the above, we aren't using HCl(aq)

0.2M

10: The following data was collected by a student performing the DETERMINING THE SPECIFIC HEAT CAPACITY AND MOLAR HEAT CAPACITY OF COPPER portion of the experiment. A 35.23g copper coil is removed from boiling water and is immediately immersed in a calorimeter with a constant of 61.3J/0C. The calorimeter contains 73.20g of water that is initially at 23.480C. The system reaches equilibrium at a temperature of 26.090C. What is the specific heat of the copper? (Specific heat of water is 4.184 J/g0C., Molar mass of copper= 65.39 g/mol) 0.398 J/g0C 0.382 J/g0C 0.407 J/g0C 0.372 J/g0C 0.368 J/g0C 26.0 J/mol0C 25.0 J/mol0C 26.6 J/mol0C 24.3 J/mol0C 24.1 J/mol0Cc

0.368 J/g0C

30: One possible method for the determination of glucose concentration is based on the formation of a blue-green complex of glucose with o-toluidine in glacial acetic acid. The reaction is as follows: HOCH2(CHOH)4CHO(glucose) + H2N(C6H4)CH3 (o-toluidine)↔ HOCH2(CHOH)4CH=N(C6H4)CH3(blue-green complex) + H2O A stock solution was prepared by dissolving and diluting 0.725g of glucose (MM=180.156g/mol) to 100.00mL with deionized water. A dilution was prepared from the stock solution by treating 30.00mL of the stock solution with o-toluidine and diluting to 100.00mL with deionized water. Colorimetric determination gave that the transmittance of the sample was 30.9% when the path length of the light through the solution was exactly 1cm. Calculate the Absorbance for the species. 0.251 1.49 3.17 0.149 0.510 0.0149 2.04 2.51 1.43 None of the above because the units are missing None of the above because the values are wrong j & k

0.510

1: Put the steps to measure a solid sample on a balance in order: Choose the balance that gives the most precise and accurate results based on the allowable capacity. Carefully brush any spilled reagent away from the balance plate. Ask your instructor for help if necessary. Wait for the reading to stabilize as much as possible before recording the mass. Tare a weighing boat on the balance Place your sample in the weighing boat. If massing crystals or powder, carefully add solid reagent using a spatula until your desired mass is reached. Dispose of your weighing boat as appropriate. If using an analytical balance, close the windows. Remove your weighing boat. 1,2,3,4,5,6,7,8,9 9,8,7,6,5,4,3,2,1 1,4,5,6,8,3,9,2,7 4,5,3,9,2,1,5,6,8,7

1,4,5,6,8,3,9,2,7

33: One possible method for the determination of glucose concentration is based on the formation of a blue-green complex of glucose with o-toluidine in glacial acetic acid. The reaction is as follows: HOCH2(CHOH)4CHO(glucose) + H2N(C6H4)CH3 (o-toluidine)↔ HOCH2(CHOH)4CH=N(C6H4)CH3(blue-green complex) + H2O A stock solution was prepared by dissolving and diluting 0.725g of glucose (MM=180.156g/mol) to 100.00mL with deionized water. A dilution was prepared from the stock solution by treating 25.00mL of the stock solution with o-toluidine and diluting to 100.00mL with deionized water. What is the concentration of the dilution? 1.01x10-2M 1.61x10-1M 5.23x103M 4.02x10-4M 1.61 M 6.21x10-1M 1.01x10-3M 4.02x10-1M 3.23x102M 6.21x102M 1.01x10-5M 4.02x10-2 M None of the above

1.01x10-2M

3: An analysis of generic antacid tablets labeled to contain 750mg of CaCO3 (MM= 100.09g/mol) per tablet of active ingredient was performed. The analysis was performed by dissolving a 0.985g sample of the antacid tablet in 90.00mL of 0.175M HCl. The excess acid was back-titrated with exactly 33.15mL of 0.155M NaOH. The average weight of a tablet is 1.025g. The tablet came from a bottle of 175 tablets that cost $4.99. Calculate the moles of HCl neutralized by the sample. 1.10x10-2 mol 1.58x10-2mol 1.06x10-2 mol 2.09x10-2 mol 5.14x10-3 mol 1.08x10-2 mol

1.06x10-2 mol

32: One possible method for the determination of glucose concentration is based on the formation of a blue-green complex of glucose with o-toluidine in glacial acetic acid. The reaction is as follows: HOCH2(CHOH)4CHO(glucose) + H2N(C6H4)CH3 (o-toluidine)↔ HOCH2(CHOH)4CH=N(C6H4)CH3(blue-green complex) + H2O A stock solution was prepared by dissolving and diluting 0.875g of glucose (MM=180.156g/mol) to 100.00mL with deionized water. A dilution was prepared from the stock solution by treating 24.00mL of the stock solution with o-toluidine and diluting to 100.00mL with deionized water. What is the concentration of the dilution? 2.02 M 4.86x10-4M 2.02x10-1M 4.94x102M 1.17x10-5M 4.86x10-2M 1.17x10-2M 6.57x103M 4.94x10-1M 1.17x10-3M 4.86x10-1M 3.78x102M None of the above

1.17x10-2M

7: The bottom of the meniscus of your solution falls exactly on the second marking from the 12mL mark of the nine markings between the 12mL and 13mL mark on your buret. How would you report this volume? 12mL 13mL 12.2mL 12.3mL 12.20mL 12.30mL 12.22mL 12.32mL 12.25mL 12.35mL 12.250mL 12.350mL

12.20 mL

14: The bottom of the meniscus of your solution falls halfway between the second and third marking from the 12mL mark of the nine markings between the 12mL and 13mL mark on your buret. How would you report this volume? 12mL 13mL 12.2mL 12.3mL 12.20mL 12.30mL 12.22mL 12.32mL 12.25mL 12.35mL 12.250mL 12.350mL

12.25 mL

15: Suppose that you titrate a 100mg vitamin C tablet and it turns out to contain only 95.5mg of vitamin C. Further, it took 26.32mL of DCP solution to reach the end point of that titration. Next, you titrate a sample of orange juice, with the end point occurring after 42.64mL of DCP solution is added. How many milligrams of vitamin c were in the sample of orange juice? 11.75mg 11.8mg 154.7mg 155mg 0.08509mg 0.0851mg There is not enough information provided to calculate the answer

155mg

43: Students performed a procedure similar to Part III of this experiment (Analyzing a Vitamin Supplement for Vitamin C Content) as described in the procedure section. A 1.078g vitamin C tablet is crushed, treated, and diluted to 100.00mL in a volumetric flask with deionized water. Three 5.00mL samples of this solution are titrated with DCP that had a standardized concentration of 9.98x10-4M. The three titrations took an average of 49.68mL of DCP. (MM Ascorbic Acid = 176.124 g/mol) Calculate the mass (in mg) in the vitamin C tablet. (MM Ascorbic Acid = 176.124 g/mol) 8.73x10-3 mg 8.73 mg 87.3 mg 873 mg 175 mg 1.75x103 mg 0.175mg mg 4.96x102 mg 4.96x10-5 mg 9.92x10-4 mg 9.92x10-3 mg

175 mg,

5: The following data was collected by a student performing the DETERMINING THE SPECIFIC HEAT CAPACITY AND MOLAR HEAT CAPACITY OF COPPER portion of the experiment. A 37.83g copper coil is removed from boiling water and is immediately immersed in a calorimeter with a constant of 63.1J/0C. The calorimeter contains 78.31g of water that is initially at 21.490C. The system reaches equilibrium at a temperature of 24.190C. What is the molar heat capacity of the copper? (Specific heat of water is 4.184 J/g0C., Molar mass of copper= 65.39 g/mol) 0.395 J/g0C 0.413 J/g0C 0.402 J/g0C 0.385 J/g0C 0.366 J/g0C 25.8 J/mol0C 27.0 J/mol0C 26.3 J/mol0C 25.2 J/mol0C 24.1 J/mol0C

24.1 J/mol0C

37: An analysis of generic antacid tablets labeled to contain 750mg of CaCO3 (MM= 100.09g/mol) per tablet of active ingredient was performed. The analysis was performed by dissolving a 0.985g sample of the antacid tablet in 90.00mL of 0.175M HCl. The excess acid was back-titrated with exactly 33.15mL of 0.155M NaOH. The average weight of a tablet is 1.025g. The tablet came from a bottle of 175 tablets that cost $4.99. Calculate the % relative error for the mg CaCO3 tablet found compared to the labeled content. 195% 29.4% 26.3% 35.7% 29.2% 41.6% 97.2% 47.4% 183% 41.2% 34.3% 32.1% 64.7% 66.1%

26.3%

9: Place the following steps for lighting a Bunsen burner in their correct order: 1. A striker positioned above the burner can be used to ignite the gas. 2. Check that the gas valve is open on the Bunsen burner. 3. Make sure that the connections are secure at both the gas outlet and at the burner. 4. The tip of the inner core of the flame should be at the base of the glassware. 5. Turn on the gas outlet and listen for the flow of gas. 6. Adjust the gas valve and the air flow regulator on the burner until the flame is about two inches in height. 1,2,3,4,5,6 3,2,5,1,6,4 6,5,4,3,2,1 3,2, 5,6,4,1

3,2,5,1,6,4

20: The correct procedure for transferring liquid with a volumetric pipet. First, rinse with tap water and do a second rinse with deionized water. Compress the rubber bulb and place it carefully over the upper end of the pipet. The bulb only needs to cover the end of the pipet to create an airtight seal, there is no need to push the pipet farther into the bulb. You may want to lubricate the hole of the rubber bulb with a drop of deionized water. Place the tip of the pipet in the liquid and draw the liquid into the pipet and above the calibration line. Keep the pipet tip submerged to avoid air bubble entry. Be careful not to draw the liquid into the bulb. Dispose of this first amount of liquid into a waste beaker. Once again, draw in the liquid to be measured above the calibration line in the pipet. Remove the bulb while simultaneously covering the tip of the pipet with your finger. Now allow the liquid level to drop to the required level by slowly allowing air to enter the pipet by a controlled lifting of the finger that is covering the end of the pipet. When the liquid level is at the correct place, move the pipet tip to the glassware where you want the liquid delivered and release your finger. Allow the pipet to drain into the container and touch off any last drop on the pipet side of the glassware. There may be some liquid remaining in the pipet tip. Do no blow this remaining liquid from the pipet. The pipet was calibrated to deliver the correct volume with this liquid remaining. How many times should you rinse a pipet before transferring liquid? 2- once with tap water and once with deionized water. 2- once with deionized water and once with the solution being transferred. 3- once with tap water, once with deionized water, and once (or twice) with the solution being transferred. 1- once with deionized water.

3- once with tap water, once with deionized water, and once (or twice) with the solution being transferred.

14: An analysis of generic antacid tablets labeled to contain 750mg of CaCO3 (MM= 100.09g/mol) per tablet of active ingredient was performed. The analysis was performed by dissolving a 0.985g sample of the antacid tablet in 90.00mL of 0.175M HCl. The excess acid was back-titrated with exactly 33.15mL of 0.155M NaOH. The average weight of a tablet is 1.025g. The tablet came from a bottle of 175 tablets that cost $4.99. Calculate the actual mg per tablet of CaCO3 in the generic antacid. 5.31x10-3 mg 2.21x10-2 mg 21.2 mg 0.531 mg 531 mg 0.553 mg 553 mg 1.06 mg 1.06x103 mg 1.11 mg 1.10x103 mg 2.12 mg 2.12x103 mg 2.21 mg 2.21x103 mg

553 mg

21: 22.1.The following data was collected by a student performing the DETERMINING THE MOLAR ENTHALPY OF SOLUTION OF AN AQUEOUS IONIC SALT portion of the experiment. A 2.97g sample of an aqueous ionic salt with a molar mass of 104.2g/mol is added to a calorimeter (Ccal= 69.7J/°C) containing 75.94g of deionized water. The water is initially at 24.700C, after adding the ionic salt, the system reaches equilibrium at a temperature of 20.310C. What is the molar enthalpy of the salt solution in kJ/mol? (Assume the specific heat of the solution is the same as pure water, 4.184 J/g0C). 306 kJ/mol 1.45x103 kJ/mol 1.76x103 kJ/mol 1.76x103 kJ/mol 1.76x106 kJ/mol 0.0285 kJ/mol 5.97x104 kJ/mol 59.7 kJ/mol 5.97x107 kJ/mol 1.70x103 kJ/mol 1.70x106 kJ/mol 1.70 kJ/mol 6.16x104 kJ/mol 61.6 kJ/mol 6.16x107 kJ/mol

61.6 kJ/mol

35: A student based the analysis of Cu(II) in a sample on the formation of the blue complex [Cu(H2O)6]+2. A standard solution was made when 1.276g of pure copper wire (MM= 63.546g/mol) was weighed, dissolved in concentrated HNO3, and diluted to 1.00x102mL. The stock solution was used to make a dilution by mixing 4.00mL of stock solution with 46.0mL of deionized water. Colorimetric determination gave that the absorbance of the sample was 0.1776 when the path length of the light through the solution was exactly 1cm. Calculate the transmittance of the solution. 3.482% 5.917% 6.187% 16.36% 26.61% 36.18% 36.73% 56.75% 59.95% 66.13% 66.44% 70.71% 77.43% 80.59% 81.33% 84.09% None of the above

66.44%

25: Students performed a procedure similar to Part II of this experiment (Analyzing Juices for Vitamin C Content) as described in the procedure section. Three 15.00mL samples of juice were titrated with DCP that had a standardized concentration of 9.92x10-4M. The three titrations took an average of 15.31mL of DCP. Calculate the mass (in mg) in 50.00mL of juice. (MM Ascorbic Acid = 176.124 g/mol) 0.178mg 1.78x10-4 mg 1.52x10-5 mg 1.52x10x10-6 mg 8.92mg 8.92x10-3 mg 178 mg 2.68mg 2.68x10-3mg 2.68x10-6 mg

8.92mg

7: The following data was collected by a student performing the DETERMINING THE CALORIMETER CONSTANT portion of the experiment. 50.00g of hot water is mixed with 50.00g of cold water Interpolating back to the time of mixing shows that the temperature of the hot water was 38.770C, the temperature of the cold water was 21.950C, and the temperature of the mixture was 28.990C. The specific heat of water is 4.184 J/g0C. What is the calorimeter constant, Ccal? -81.4 J/0C 81.4 J/0C -58.6 J/0C 58.6 J/0C -573 J/0C 573 J/0C 3.52x103 J/0C -3.52x103 J/0C 1.47x103 J/0C -1.47x103 J/0C -2.05x103 J/0C 2.05x103 J/0C 7.04 J/0C -7.04 J/0C 9.78 J/0C -9.78 J/0C

81.4 J/0C

24: One possible method for the determination of glucose concentration is based on the formation of a blue-green complex of glucose with o-toluidine in glacial acetic acid. The reaction is as follows: HOCH2(CHOH)4CHO(glucose) + H2N(C6H4)CH3 (o-toluidine) ↔ HOCH2(CHOH)4CH=N(C6H4)CH3(blue-green complex) + H2O A stock solution was prepared by dissolving and diluting 0.875g of glucose (MM=180.156g/mol) to 100.00mL with deionized water. Eight standard solutions were prepared by treating different volumes of the stock solution with o-toluidine and diluting to 100.00mL with deionized water. Also treated with the reagent o-toluidine was an unknown blood serum solution for analysis. A researcher measured the % transmittance of the eight dilutions and used the information to prepare a Beer's Law calibration curve. The volumes of stock solution used to prepare the dilutions and their % transmittances are given below. The path length, b, of the light through the solution was exactly 1cm. Volume Stock glucose, ml %T 3.00

82.3 6.00 67.9 9.00 55.4 12.00 46.9 15.00 37.5 18.00 31.7 21.00 25.8 24.00 22.5 Blood Sample: 35.4 Using the above information, prepare a properly labeled Beer's Law plot using your LoggerPro© software. Perform a linear fit for the data. Using the data provided determine the concentration of glucose in the blood sample: determine the absorbance of the sample and use the "Interpolation Calculator" or "Interpolate" function (under the ANALYZE drop-down menu) to determine the concentration from the standard Beer's Law plot you generated. Print out your graph showing the linear fit AND the interpolation. You will turn this in to your lab instructor when you perform this experiment. Make sure the graph has properly labeled axes, a title, and includes your name, lab locker #, and date (these can be added in the "print footer" boxes under Print Options). These must be printed with the graph and should not be added by hand to receive credit. Using the Beer's Law plot you generated: determine the molar absorptivity for this species; and the absorbance and concentration of glucose in the blood sample. Select your answers from the list below. (Concentrations and molar absorptivities are given to two significant figures). Type: Multiple Select Points Awarded: 0.333/1 Your Answer(s): 56 cm-1M-1 Correct Answer(s): 0.018 cm-1M-1 0.022 cm-1M-1 0.024 cm-1M-1 0.027 cm-1M-1 37 cm-1M-1 42 cm-1M-1 45 cm-1M-1 56 cm-1M-1 (correct) 0.451 (correct) 0.274 0.277 0.361 0.274 A 0.277A 0.361 A 0.451 A 4.2x10-3 M 7.2x10-3 M 7.9x10-3 M (correct) 8.5x10-3 M None of the above

34: Students performed Part I of this experiment (Standardizing the DCP solution) as described in the procedure section. The weight of the reagent grade AA that was 48.51mg. The AA was diluted to 50.00mL in a volumetric flask. Three 5.00mL portions of the AA solution were titrated with 28.04, 27.23, and 27.86mL of DCP respectively. Calculate the average molarity of the DCP solution and the standard deviation associated with these measurements. Check your two answers. (MM Ascorbic Acid = 176.124 g/mol) 9.82x10-4 M 9.82x10-7 M 9.88x10-4 M 9.88x10-7 M 9.94x10-4 M 9.94x10-7 M 1.01x10-3 M 1.01x10-6 M 1.54x10-5 M 1.54x10-8 M 1.25x10-5 M 1.25x10-8 M 2.75x10-4 M 2.75x10-7 M 5.51x10-3 M 5.51x10-6 M

9.94x10-4 M, 1.54x10-5 M

10: What are some things to keep in mind when using a hot plate? Always assume the hotplate is hot, even when it's off. Do not touch the surface of the hot plate. Never leave anything on the hot plate unattended. Keep the hot plate away from the sinks. Keep the power cord of the hot plate away from the heated surface to avoid damaging the cord. Keep the power cord of the hot plate away from the sink. ALL OF THE ABOVE

ALL OF THE ABOVE

5: Is texting on your cell phone is permitted in lab? Sure! Absolutely not

Absolutely not

10: Eye Protection: Students are required to bring goggles. Goggles must be approved and full splash-proof Goggles MUST be worn at all times in the lab All of the above

All of the above

22: What are the precautions we need to take when handling sodium hydroxide in the Intro to Lab Quest © experiment? Wear approved splash-proof goggles at all times Wear approved non-latex gloves at all times Avoid skin contact Avoid inhalation Tie back long hair Wear appropriate lab attire All of the above. a and b only a-d but not e and f.

All of the above

26: What is included in a properly labeled graph? Graph Title Labeled Axes You and your partner's names Your lab bench number All of the above

All of the above

28: An analytical balance: Have a smaller total capacity than top-loading balances Have greater precision than top-loading balances. Are in a glass enclosure to minimize the effect of air movement. All of the above

All of the above

2: What do you do if you receive a chemical splash to the eyes? Do not rub or wipe the eyes Walk, don't run to the nearest eyewash station At the eyewash fountain, hold the eyelids open with the thumb and forefinger Let the water flow into the eyes continuously for fifteen minutes or until medical help arrives. All of the above.

All of the above

31: Required attire in the lab includes: Approved Goggles Non- latex Gloves Closed-toe shoes that do not leave the top of the foot exposed Long Pants Lab Coat All of the above a,b,c, and d are correct

All of the above

34: What are the precautions we need to take when handling hydrochloric acid in the Intro to Lab Quest © Experiment? Wear approved splash-proof goggles at all times Wear approved non-latex gloves at all times Avoid skin contact Avoid inhalation Tie back long hair Wear appropriate lab attire All of the above. a and b only a-d but not e and f.

All of the above

38: What do we mean by "waste minimization?" We try to use as little reagents as possible during the experiment. We take only the amounts of reagents necessary to complete the experiment. We dispose of waste in proper containers. We do not return excess waste to the reagent bottles. All of the above.

All of the above

32: When using a balance: Always use a weighing boat or beaker when massing solid or liquid samples. Never attempt to move the balance. Always close glass doors on an analytical balance before recording mass. Use a brush to clean any spilled solid reagent. Wait for the balance to stabilize before recording your reading. Try to use the same balance throughout the experiment to eliminate calibration error. Dispose of your weighing boat properly, do not leave it on the bench top. All of the above!

All of the above!

9: When using a balance: Always use a weighing boat or beaker when massing solid or liquid samples. Never attempt to move the balance. Always close glass doors on an analytical balance before recording mass. Use a brush to clean any spilled solid reagent. Wait for the balance to stabilize before recording your reading. Try to use the same balance throughout the experiment to eliminate calibration error. Dispose of your weighing boat properly, do not leave it on the bench top. All of the above!

All of the above!

23: What are the precautions we need to take when handling the solutions in the Back Titration experiment? Wear approved splash-proof goggles at all times Wear approved non-latex gloves at all times Avoid skin contact Avoid inhalation Avoid ingestion Tie back long hair Wear appropriate lab attire All of the above. a and b only a-e but not f and g.

All of the above.

31: What do we mean by "waste minimization?" We try to use as little reagents as possible during the experiment. We take only the amounts of reagents necessary to complete the experiment. We dispose of waste in proper containers. We do not return excess waste to the reagent bottles. All of the above.

All of the above. (correct)

11: What is dehydroascorbic acid? An additive used to prevent the decomposition of vitamin C An ascorbic acid reduction product An ascorbic acid oxidation product An additive used in vitamin C analysis to denature and precipitate proteins An additive used in vitamin C analysis to prevent side reactions of DCP Both a and e

An ascorbic acid oxidation product

17: Why don't we titrate an antacid tablet directly with a standardized acid solution? Check all that apply. Antacids are not very soluble in acidic solutions. Antacids are not very soluble in water. Antacids are weak bases. Antacids exhibit resistance to pH change while being titrated.

Antacids are not very soluble in water. (correct) Antacids are weak bases. (correct) Antacids exhibit resistance to pH change while being titrated. (correct)

6: Required attire in the lab includes (check all that apply): Approved Goggles Non-latex gloves Closed-toe shoes that do not leave the top of the foot exposed Long Pants Lab Coat

Approved Goggles (correct) Non-latex gloves (correct) Closed-toe shoes that do not leave the top of the foot exposed (correct) Long Pants (correct) Lab Coat (correct)

38: When cleaning volumetric glassware prior to measuring As a final step before measuring, wet the inside surfaces of the glassware with deionized water. First wash with water plus detergent; second rinse thoroughly with water; third rise with deionized water. As a final step before measuring, wet the inside surfaces with the liquid being measured. a & c b & c

As a final step before measuring, wet the inside surfaces with the liquid being measured.

22: You do not know where to properly discard something. Uh oh! What should you do? Ask your instructor so that it gets disposed of properly. Take your best guess.

Ask your instructor so that it gets disposed of properly.

28: The correct procedure for transferring liquid with a volumetric pipet. First clean and rinse your pipet with tap water and do a second rinse with deionized water. If using an atomizer bulb: Compress the rubber bulb and place it carefully over the upper end of the pipet. The bulb only needs to cover the end of the pipet to create an airtight seal, there is no need to push the pipet farther into the bulb. You may want to lubricate the hole of the rubber bulb with a drop of deionized water. If using a rolling pipet top: Press the proper sized pipet top tightly onto the end of the pipet in order to create an airtight seal. Place the tip of the pipet in the liquid and draw the liquid into the pipet and above the calibration line. Keep the pipet tip submerged to avoid air bubble entry. Be careful not to draw the liquid into the bulb. Dispose of this first amount of liquid into a waste beaker. Once again, draw in the liquid to be measured above the calibration line in the pipet. If using an atomizer bulb: remove the bulb while simultaneously covering the tip of the pipet with your finger. Now allow the liquid level to drop to the required level by slowly allowing air to enter the pipet by a controlled lifting of the finger that is covering the end of the pipet. If using a rolling pipet top, there is no need to remove the top. Push the side button to allow your pipet to drain. When the liquid level is at the correct place, move the pipet tip to the glassware where you want the liquid delivered and release your finger. Allow the pipet to drain into the container and touch off any last drop on the pipet side of the glassware. There may be some liquid remaining in the pipet tip. Do no blow this remaining liquid from the pipet. The pipet was calibrated to deliver the correct volume with this liquid remaining. NEVER allow the liquid to enter the pipet top (atomizer bulb or rolling). What is the major difference between the atomizer bulb and a rolling pipet top: Atomizer bulbs should be loosely attached to the pipet to facilitate their removal when draining the pipet, where rolling pipet tops should be more tightly attached to the pipet and don't have to be removed to drain the pipet.. Atomizer bulbs have a more complicated cleaning process. Rolling pipet tops require one less rinse of the pipet.

Atomizer bulbs should be loosely attached to the pipet to facilitate their removal when draining the pipet, where rolling pipet tops should be more tightly attached to the pipet and don't have to be removed to drain the pipet..

12: Why are we cautious in the handling of acids and bases, no matter what their concentration? We only need to be cautious handling acids and bases of relatively high concentrations. Because acids and bases can react violently at any concentration.

Because acids and bases can react violently at any concentration.

34: Why are we cautious in the handling of acids and bases, no matter what their concentration? We only need to be cautious handling acids and bases of relatively high concentrations. Because acids and bases can react violently at any concentration.

Because acids and bases can react violently at any concentration.

11: A student who is determining the enthalpy of an exothermic neutralization reaction has a choice between two calorimeters: Calorimeter A has a specific heat of 100 J/g0C and weighs 50g, Calorimeter B has a specific heat of 200 J/g0C and weighs 20g. If an ideal calorimeter would absorb no heat from the reaction, which calorimeter should the student use? Calorimeter A, it will absorb less heat. Calorimeter B, it will absorb less heat. Calorimeter A, it will absorb more heat. Calorimeter B, it will absorb more heat. Either one, there is no advantage for one calorimeter or the other. There is not enough information provided to answer the question.

Calorimeter B, it will absorb less heat.

33: A student has a solution containing a mixture of metal cations: Cu+2, Cr+2, and Fe+3, each a solution with NO3- anion. Adding a concentrated solution of NH4OH(aq) caused the precipitation of Cr+2 and Fe+3 as insoluble hydroxides. The Cu+2 remained in solution and forms the complex ion Cu(NH3)4+2. Which balanced net ionic equations represent each of these reactions? Check all that apply. Cu+2(aq) + 4NH4+(aq) +4OH-(aq) → Cu(NH3)4+2(aq) + 4H2O(l) Cu+2(aq) + 4NH4+(aq) +4OH-(aq) → Cu(NH3)4+2(s) + 4H2O(l) Cu+2(aq) +2NO3-(aq) + 4NH4+(aq) + 4OH-(aq) → Cu(NH3)4+2(aq) + 2NO3-(aq) + 4H2O(l) Cu+2(aq) +2NO3-(aq) + 4NH4+(aq) + 4OH-(aq) → Cu(NH3)4+2(s) + 2NO3-(aq) + 4H2O(l) Cu(NO3)2(aq) + 4NH4OH(aq) → Cu(NH3)4+2(aq) + 2NO3-(aq) + 4H2O(l) Cu(NO3)2(aq) + 4NH4OH(aq) → Cu(NH3)4+2(s) + 2NO3-(aq) + 4H2O(l) Cr+2(aq) + 2OH-(aq) → Cr(OH)2(s) (correct) Cr+2(aq) + 2OH-(aq) → Cr(OH)2(aq) Cr+2(aq) +2NO3-(aq) + 2NH4+(aq) + 2OH-(aq) → Cr(OH)2(s) + 2NO3-(aq) + 2NH4+(aq) Cr+2(aq) +2NO3-(aq) + 2NH4+(aq) + 2OH-(aq) → Cr(OH)2(aq) + 2NO3-(aq) + 2NH4+(aq) Cr(NO3)2(aq) + 2NH4OH(aq) → 2NH4NO3(aq) + Cr(OH)2(s) Cr(NO3)2(aq) + 2NH4OH(aq) → 2NH4NO3(aq) + Cr(OH)2(aq) Fe+3(aq) + 3OH-(aq) → Fe(OH)3(s) (correct) Fe+3(aq) + 3OH-(aq) → Fe(OH)3(aq) Fe+3(aq) +3NO3-(aq) + 3NH4+(aq) + 3OH-(aq) → Fe(OH)3(s) + 3NO3-(aq) + 3NH4+(aq) Fe+3(aq) +3NO3-(aq) + 3NH4+(aq) + 3OH-(aq) → Fe(OH)3(aq) + 3NO3-(aq) + 3NH4+(aq) Fe(NO3)2(aq) + 3NH4OH(aq) → 3NH4NO3(aq) + Fe(OH)3(s) Fe(NO3)2(aq) + 3NH4OH(aq) → 3NH4NO3(aq) + Fe(OH)3(aq)

Cu+2(aq) + 4NH4+(aq) +4OH-(aq) → Cu(NH3)4+2(aq) + 4H2O(l)

15: In which parts of the experiment will we be using a balance? Check all that apply. Determining the Calorimeter Constant Determine the Specific Heat and Molar Heat Capacity of Copper Determining the Molar Enthalpy of Solution of an Aqueous Ionic Salt Determining the Molar Enthalpy of Neutralization

Determine the Specific Heat and Molar Heat Capacity of Copper (correct) Determining the Molar Enthalpy of Solution of an Aqueous Ionic Salt (correct)

1: In which parts of the experiment will we be using a volumetric pipet? Check all that apply. Determining the Calorimeter Constant Determine the Specific Heat and Molar Heat Capacity of Copper Determining the Molar Enthalpy of Solution of an Aqueous Ionic Salt Determining the Molar Enthalpy of Neutralization

Determining the Molar Enthalpy of Neutralization

18: According to the procedure in this experiment, you will dissolve an antacid tablet into a specific amount of hydrochloric acid solution, and then add an acid-base indicator. After the titration, the indicator should show the resulting solution is: Basic Neutral Acidic Oxidizing Either a or b

Either a or b

26: Your cell-phone is permitted in lab. TRUE FALSE

FALSE

9: Your cell-phone is permitted in lab. TRUE FALSE

FALSE

35: You are permitted to bring food or drink into the lab, as long as it's packaged and you don't eat or drink it while in the lab. TRUE FALSE

False

36: You are permitted to bring food or drink into the lab, as long as it's packaged and you don't eat or drink it while in the lab. TRUE FALSE

False

38: Gloves can be disposed of in the regular trash TRUE FALSE

False

42: Gloves can be disposed of in the regular trash TRUE FALSE

False

38: A student has a solution containing a mixture of metal cations: Cu+2, Cr+2, and Fe+3, each a solution with NO3- anion. Adding a concentrated solution of NH4OH(aq) caused the precipitation of Cr+2 and Fe+3 as insoluble hydroxides. The Cu+2 remained in solution and forms the complex ion Cu(NH3)4+2. Which balanced molecular equations represent each of these reactions? Check all that apply. Cu+2(aq) + 4NH4+(aq) +4OH-(aq) → Cu(NH3)4+2(aq) + 4H2O(l) Cu+2(aq) + 4NH4+(aq) +4OH-(aq) → Cu(NH3)4+2(s) + 4H2O(l) Cu+2(aq) +2NO3-(aq) + 4NH4+(aq) + 4OH-(aq) → Cu(NH3)4+2(aq) + 2NO3-(aq) + 4H2O(l) Cu+2(aq) +2NO3-(aq) + 4NH4+(aq) + 4OH-(aq) → Cu(NH3)4+2(s) + 2NO3-(aq) + 4H2O(l) Cu(NO3)2(aq) + 4NH4OH(aq) → Cu(NH3)4+2(aq) + 2NO3-(aq) + 4H2O(l) (correct) Cu(NO3)2(aq) + 4NH4OH(aq) → Cu(NH3)4+2(s) + 2NO3-(aq) + 4H2O(l) Cr+2(aq) + 2OH-(aq) → Cr(OH)2(s) Cr+2(aq) + 2OH-(aq) → Cr(OH)2(aq) Cr+2(aq) +2NO3-(aq) + 2NH4+(aq) + 2OH-(aq) → Cr(OH)2(s) + 2NO3-(aq) + 2NH4+(aq) Cr+2(aq) +2NO3-(aq) + 2NH4+(aq) + 2OH-(aq) → Cr(OH)2(aq) + 2NO3-(aq) + 2NH4+(aq) Cr(NO3)2(aq) + 2NH4OH(aq) → 2NH4NO3(aq) + Cr(OH)2(s) (correct) Cr(NO3)2(aq) + 2NH4OH(aq) → 2NH4NO3(aq) + Cr(OH)2(aq) Fe+3(aq) + 3OH-(aq) → Fe(OH)3(s) Fe+3(aq) + 3OH-(aq) → Fe(OH)3(aq) Fe+3(aq) +3NO3-(aq) + 3NH4+(aq) + 3OH-(aq) → Fe(OH)3(s) + 3NO3-(aq) + 3NH4+(aq) Fe+3(aq) +3NO3-(aq) + 3NH4+(aq) + 3OH-(aq) → Fe(OH)3(aq) + 3NO3-(aq) + 3NH4+(aq) Fe(NO3)3(aq) + 3NH4OH(aq) → 3NH4NO3(aq) + Fe(OH)3(s) Fe(NO3)2(aq) + 3NH4OH(aq) → 3NH4NO3(aq) + Fe(OH)3(aq)

Fe(NO3)3(aq) + 3NH4OH(aq) → 3NH4NO3(aq) + Fe(OH)3(s)

32: A student has a solution containing a mixture of metal cations: Cu+2, Cr+2, and Fe+3, each a solution with NO3- anion. Adding a concentrated solution of NH4OH(aq) caused the precipitation of Cr+2 and Fe+3 as insoluble hydroxides. The Cu+2 remained in solution and forms the complex ion Cu(NH3)4+2. Which balanced complete ionic equations represent each of these reactions? Check all that apply. Cu+2(aq) + 4NH4+(aq) +4OH-(aq) → Cu(NH3)4+2(aq) + 4H2O(l) Cu+2(aq) + 4NH4+(aq) +4OH-(aq) → Cu(NH3)4+2(s) + 4H2O(l) Cu+2(aq) +2NO3-(aq) + 4NH4+(aq) + 4OH-(aq) → Cu(NH3)4+2(aq) + 2NO3-(aq) + 4H2O(l) (correct) Cu+2(aq) +2NO3-(aq) + 4NH4+(aq) + 4OH-(aq) → Cu(NH3)4+2(s) + 2NO3-(aq) + 4H2O(l) Cu(NO3)2(aq) + 4NH4OH(aq) → Cu(NH3)4+2(aq) + 2NO3-(aq) + 4H2O(l) Cu(NO3)2(aq) + 4NH4OH(aq) → Cu(NH3)4+2(s) + 2NO3-(aq) + 4H2O(l) Cr+2(aq) + 2OH-(aq) → Cr(OH)2(s) Cr+2(aq) + 2OH-(aq) → Cr(OH)2(aq) Cr+2(aq) +2NO3-(aq) + 2NH4+(aq) + 2OH-(aq) → Cr(OH)2(s) + 2NO3-(aq) + 2NH4+(aq) (correct) Cr+2(aq) +2NO3-(aq) + 2NH4+(aq) + 2OH-(aq) → Cr(OH)2(aq) + 2NO3-(aq) + 2NH4+(aq) Cr(NO3)2(aq) + 2NH4OH(aq) → 2NH4NO3(aq) + Cr(OH)2(s) Cr(NO3)2(aq) + 2NH4OH(aq) → 2NH4NO3(aq) + Cr(OH)2(aq) Fe+3(aq) + 3OH-(aq) → Fe(OH)3(s) Fe+3(aq) + 3OH-(aq) → Fe(OH)3(aq) Fe+3(aq) +3NO3-(aq) + 3NH4+(aq) + 3OH-(aq) → Fe(OH)3(s) + 3NO3-(aq) + 3NH4+(aq) Fe+3(aq) +3NO3-(aq) + 3NH4+(aq) + 3OH-(aq) → Fe(OH)3(aq) + 3NO3-(aq) + 3NH4+(aq) Fe(NO3)2(aq) + 3NH4OH(aq) → 3NH4NO3(aq) + Fe(OH)3(s) Fe(NO3)2(aq) + 3NH4OH(aq) → 3NH4NO3(aq) + Fe(OH)3(aq)

Fe+3(aq) +3NO3-(aq) + 3NH4+(aq) + 3OH-(aq) → Fe(OH)3(s) + 3NO3-(aq) + 3NH4+(aq)

29: Which is not true about an analytical balance? Have a greater total capacity than top-loading balances Rationale: Please refer to Appendix III of your lab manual. Have greater precision than top-loading balances. Are in a glass enclosure to minimize the effect of air movement. All of the above are correct.

Have a greater total capacity than top-loading balances (correct)

17: If you dissolve a certain ionic salt in water, the solution temperature drops. What is happening in thermodynamic terms? Heat is leaving the system and the reaction is exothermic. Heat is leaving the system and the reaction is endothermic. Heat is entering the system and the reaction is exothermic. Heat is entering the system and the reaction is endothermic.

Heat is entering the system and the reaction is endothermic.

19: Precision is a measure of: Accuracy. How close a series of measurements are to each other. Rationale: Please refer to Appendix I of your lab manual. The quality of the work the lab technician is doing. The quality of the instrument used to do the measurement.

How close a series of measurements are to each other.

35: Precision is a measure of: Accuracy How close a series of measurements are to each other. Rationale: Incorrect Note: Please refer to Appendix I of your lab manual. The quality of the work the lab technician is doing. The quality of the instrument used to do the measurement.

How close a series of measurements are to each other.

18: An MSDS includes what information about a chemical? Check all that apply Identity Ingredients Physical and chemical characteristics Physical Hazards Health Hazards Proper Storage and Disposal

Identity (correct) Ingredients (correct) Physical and chemical characteristics (correct) Physical Hazards (correct) Health Hazards (correct) Proper Storage and Disposal (correct)

39: In the titration part of our experiment with a buret: Record the pH after every 5mL of NaOH is added until the titration is complete. Record the pH after every 1mL of NaOH is added until the titration is complete. The titration is complete at the endpoint. If you overshoot the endpoint of pH 7.0, record the volume of NaOH added and the pH closes to the equivalence point.

If you overshoot the endpoint of pH 7.0, record the volume of NaOH added and the pH closes to the equivalence point.

20: When is the best time to clean equipment and tools in the lab? At the end of the experiment Immediately after use At the beginning of your next experiment Never, the stock room will take care of it

Immediately after use

32: Broken Glass, Disposable Pipets, and gloves are all discarded: In the regular trash. In special, labeled, thick-walled containers that are located throughout the lab In the liquid hazardous waste drum. Outside of the lab.

In special, labeled, thick-walled containers that are located throughout the lab

9: Broken Glass, Disposable Pipets, and gloves are all discarded: In the regular trash. In special, labeled, thick-walled containers that are located throughout the lab In the liquid hazardous waste drum. Outside of the lab.

In special, labeled, thick-walled containers that are located throughout the lab

26: Uh oh! You accidently knocked over an empty beaker, and it's shattered. What should you do? Pick up the pieces by hand and dispose of them immediately in the garbage. Use a broom to sweep up the glass shards and dispose of them in the garbage. Inform an instructor immediately, who will sweep up the glass shards and dispose of them in a thick-walled carton container. Wait until after the lab to notify your instructor.

Inform an instructor immediately, who will sweep up the glass shards and dispose of them in a thick-walled carton container.

2: What is significant about the sulfuric acid used in the Qualitative Analysis Experiment? It's a more concentrated chemical than we usually handle in lab, and needs to be handled with extra care: drops will be added to your reaction mixture directly from a dropper bottle. You will NOT pour this concentrated chemical from its container into a beaker. It is much less concentrated, and can be disposed of in the drain.

It's a more concentrated chemical than we usually handle in lab, and needs to be handled with extra care: drops will be added to your reaction mixture directly from a dropper bottle. You will NOT pour this concentrated chemical from its container into a beaker.

37: What is significant about the ammonium hydroxide used in the Qualitative Analysis Experiment? It's a more concentrated chemical than we usually handle in lab, and needs to be handled with extra care: drops will be added to your reaction mixture directly from a dropper bottle. You will NOT pour this concentrated chemical from its container into a beaker. It is much less concentrated, and can be disposed of in the drain.

It's a more concentrated chemical than we usually handle in lab, and needs to be handled with extra care: drops will be added to your reaction mixture directly from a dropper bottle. You will NOT pour this concentrated chemical from its container into a beaker.

3: We have used HCl (aq) many times in the lab before. What's different about the HCl(aq) being used in the Qualitative Analysis experiment? It's much more concentrated, and needs to be handled with extra care: drops will be added to your reaction mixture directly from a dropper bottle. You will NOT pour this concentrated chemical from its container into a beaker. It is much less concentrated, and can be disposed of in the drain.

It's much more concentrated, and needs to be handled with extra care: drops will be added to your reaction mixture directly from a dropper bottle. You will NOT pour this concentrated chemical from its container into a beaker.

23: A special receptacle for the disposal of gloves, broken glass and other solid waste is: Located at several places throughout the lab Located in the hall Located at the White Drum Does not exist. These may be discarded in the trash.

Located at several places throughout the lab

28: A special receptacle for the disposal of gloves, broken glass and other solid waste is: Located at several places throughout the lab Located in the hall Located at the White Drum Does not exist. These may be discarded in the trash.

Located at several places throughout the lab

1: When disposing of solutions: First dispose of the chemical into your waste beaker or the white drum. Second, rinse with tap water, this rinse should be disposed of as hazardous waste. Third, rinse with tap water a second time. This rinse should also be disposed of as hazardous waste. Any further rinses can be disposed of in the sink. Finally, continue cleaning with brush and detergent as described in Appendix III. Given the above information, after disposing of your chemical in a waste beaker or the white drum, you rinse your beaker with tap water. Can this rinse water be disposed of in the sink? Sure. No

No

30: When disposing of solutions: First dispose of the chemical into your waste beaker or the white drum. Second, rinse with tap water, this rinse should be disposed of as hazardous waste. Third, rinse with tap water a second time. This rinse should also be disposed of as hazardous waste. Any further rinses can be disposed of in the sink. Finally, continue cleaning with brush and detergent as described in Appendix III. Given the above information, after disposing of your chemical in a waste beaker or the white drum, you rinse your beaker with tap water. Can this rinse water be disposed of in the sink? Sure. No

No

11: We are given an unknown antacid pill and through the procedure in this lab we determine its cost effectiveness to be 5.0x10-1 mole of acid/$. Can we also determine the number of moles of base in the pill? Yes, we simply write a balanced chemical equation No, because antacid tablets are a formulation of unknown compounds Sometimes it's possible with pure antacids None are correct

No, because antacid tablets are a formulation of unknown compounds

12: When disposing of solutions: First dispose of the chemical into your waste beaker or the white drum. Second, rinse with tap water, this rinse should be disposed of as hazardous waste. Third, rinse with tap water a second time. This rinse should also be disposed of as hazardous waste. Any further rinses can be disposed of in the sink. Finally, continue cleaning with brush and detergent as described in Appendix III. Given the above information, after disposing of your chemical in a waste beaker or the white drum, you rinse your beaker with tap water. Can this rinse water be disposed of in the sink? Sure. No, the rinse water is still contaminated with possibly harmful chemicals. It, and the following rinse, should be disposed of as hazardous waste.

No, the rinse water is still contaminated with possibly harmful chemicals. It, and the following rinse, should be disposed of as hazardous waste.

31: The correct procedure for preparation of a buret for titration of a strong acid with a strong base: 1. First clean the buret with tap water and a buret brush (if available). 2. Rinse the interior of the buret with tap water. 3. Rinse the interior of the buret with deionized water. 4. Rinse the interior of the buret with about 5mL of your titrant, dispose of this aliquot in your waste beaker. To properly wet the inside surfaces, tip the buret on its side while holding it in your hand. Be careful not to spill the solution (you can use parafilm to cover the open end of the buret). Make sure the solution comes into contact with every surface in the interior of the buret by rotating the buret. Drain the rinse solution through the stopcock into the waste beaker. 5. Rinse the interior of the buret with about 5mL of your titrant as above. Also dispose of this aliquot in your waste beaker. 6. Check the stopcock for leaks. Make sure it is not loose. 7. When filling the buret, do so at eye level and always use a funnel. You may need to unclip the buret from the stand when filling or refilling. 8. Make sure the stopcock is closed, and that you not pouring a chemical above eye level. Use a funnel and fill the buret above the 0.0 mark with titrant. Be careful that you do not overfill the buret. 9. Clip the buret to the stand, making sure it is perfectly vertical. Drain the buret carefully through the stopcock until the buret reads 0.00mL. 10. Place a beaker underneath the full buret in case the stopcock comes loose. Always keep a beaker underneath a buret that has titrant in it. Which is incorrect? Always use a funnel when filling a buret. Never pour chemicals above eye level! Unclip the buret from the stand when filling. Always check the stopcock for leaks before filling the buret. Always keep a beaker underneath a buret with a liquid in it. Make sure the buret is perfectly vertical when reading it. None of the above are incorrect.

None of the above are incorrect.

32: The correct procedure for preparation of a buret for titration of a strong acid with a strong base: First, rinse the interior of the buret with tap water. Rinse the interior of the buret with deionized water. Rinse the interior of the buret with about 5mL of your titrant, dispose of this aliquot in your waste beaker. To properly wet the inside surfaces, tip the buret on its side while holding it in your hand. Be careful not to spill the solution (you can use parafilm to cover the open end of the buret). Make sure the solution comes into contact with every surface in the interior of the buret by rotating the buret. Drain the rinse solution through the stopcock into the waste beaker. Rinse the interior of the buret with about 5mL of your titrant as above. Also dispose of this aliquot in your waste beaker. Check the stopcock for leaks. Make sure it is not loose. When filling the buret, do so at eye level and always use a funnel. You may need to unclip the buret from the stand when filling or refilling. Make sure the stopcock is closed, and that you not pouring a chemical above eye level. Use a funnel and fill the buret above the 0.0 mark with titrant. Be careful that you do not overfill the buret. Clip the buret to the stand, making sure it is perfectly vertical. Drain the buret carefully through the stopcock until the buret reads 0.00mL. Place a beaker underneath the full buret in case the stopcock comes loose. Always keep a beaker underneath a buret that has titrant in it. Which is incorrect? Always use a funnel when filling a buret. Never pour chemicals above eye level! Unclip the buret from the stand when filling. Always keep a beaker underneath a buret with a liquid in it. Make sure the buret is perfectly vertical when reading it. None of the above are incorrect.

None of the above are incorrect.

5: 1.1. The correct procedure for preparation of a buret for titration of a strong acid with a strong base: 1. First clean the buret with approved laboratory glassware cleaner and a buret brush (if available). 2. Rinse the interior of the buret with tap water. 3. Rinse the interior of the buret with deionized water. 4. Rinse the interior of the buret with about 5mL of your titrant, dispose of this aliquot in your waste beaker. To properly wet the inside surfaces, tip the buret on its side while holding it in your hand. Be careful not to spill the solution (you can use parafilm to cover the open end of the buret). Make sure the solution comes into contact with every surface in the interior of the buret by rotating the buret. Drain the rinse solution through the stopcock into the waste beaker. 5. Rinse the interior of the buret with about 5mL of your titrant as above. Also dispose of this aliquot in your waste beaker. 6. Check the stopcock for leaks. Make sure it is not loose. 7. When filling the buret, do so at eye level and always use a funnel. You may need to unclip the buret from the stand when filling or refilling. 8. Make sure the stopcock is closed, and that you not pouring a chemical above eye level. Use a funnel and fill the buret above the 0.0 mark with titrant. Be careful that you do not overfill the buret. 9. Clip the buret to the stand, making sure it is perfectly vertical. Drain the buret carefully through the stopcock until the buret reads 0.00mL. 10. Place a beaker underneath the full buret in case the stopcock comes loose. Always keep a beaker underneath a buret that has titrant in it. Which is incorrect? Always use a funnel when filling a buret. Never pour chemicals above eye level! Unclip the buret from the stand when filling. Always check the stopcock for leaks before filling the buret. Always keep a beaker underneath a buret with a liquid in it. Make sure the buret is perfectly vertical when reading it. None of the above are incorrect.

None of the above are incorrect.

27: What concentration of sulfuric acid will we be using in the Intro to Lab Quest © Experiment? 2.0M 1.0M 0.2M 0.1M 0.02M 0.01M None of the above, we aren't using H2SO4

None of the above, we aren't using H2SO4

13: Which of the below is permitted in the lab? Bottled water for drinking Clear liquids, such as tea Coffee Soda or juice, as long as it is a closed container None of the above.

None of the above.

4: Which of the below is permitted in the lab? Bottled water for drinking Clear liquids, such as tea Coffee Soda or juice, as long as it is a closed container None of the above.

None of the above. (correct)

17: Which parts of the experiment require an automatic pipet? Select all that apply. Part I- Standardizing the DCP solution Part II- Analyzing Juices for Vitamin C Content Part III- Analyzing a Vitamin Supplement for Vitamin C content

Part I- Standardizing the DCP solution (correct) Part II- Analyzing Juices for Vitamin C Content (correct) Part III- Analyzing a Vitamin Supplement for Vitamin C content (correct)

18: Which parts of the experiment require metaphosphoric acid? Select all that apply. Part I- Standardizing the DCP solution Part II- Analyzing Juices for Vitamin C Content Part III- Analyzing a Vitamin Supplement for Vitamin C content (correct)

Part II- Analyzing Juices for Vitamin C Content

16: Which parts of the experiment require a mortar and pestle? Select all that apply. Part I- Standardizing the DCP solution Part II- Analyzing Juices for Vitamin C Content Part III- Analyzing a Vitamin Supplement for Vitamin C content

Part III- Analyzing a Vitamin Supplement for Vitamin C content

22: Which parts of the experiment require a 100mL volumetric flask? Select all that apply. Part I- Standardizing the DCP solution Part II- Analyzing Juices for Vitamin C Content Part III- Analyzing a Vitamin Supplement for Vitamin C content

Part III- Analyzing a Vitamin Supplement for Vitamin C content

8: Describe the following analysis as either quantitative, qualitative, or both: The solution, given initial concentrations, absorbs 30% of incident light. Qualitative Quantitative Both

Quantitative

33: What is the meaning of "RDA and what is the RDA of ascorbic acid for humans? RDA means recommended daily allowance and for humans is 60mg of vitamin C RDA means recommended daily allowance and for humans is 600mg of vitamin C RDA means recommended daily allowance and for humans is 6mg of vitamin C RDA means reduced daily allowance and for humans is 60mg of vitamin C RDA means reduced daily allowance and for humans is 600mg of vitamin C RDA means reduced daily allowance and for humans is 6mg of vitamin C None of the above are correct

RDA means recommended daily allowance and for humans is 60mg of vitamin C

31: How would you determine the number of significant figures when reading the volume of an aqueous solution in a buret? Read the bottom of the meniscus at eye level, and round to the nearest calibration mark on your instrument. Read the bottom of the meniscus at eye level; report your data to the nearest calibration mark and add an estimated digit Read the top of the meniscus and round to the nearest calibration mark. Read the bottom of the meniscus at eye level, and round to the nearest tenth of a mL.

Read the bottom of the meniscus at eye level; report your data to the nearest calibration mark and add an estimated digit

6: How would you determine the number of significant figures when reading the volume of an aqueous solution in a graduated cylinder? Read the bottom of the meniscus at eye level, and round to the nearest calibration mark on your instrument. Read the bottom of the meniscus at eye level; report your data to the nearest calibration mark and add an estimated digit. Read the top of the meniscus and round to the nearest calibration mark. Read the bottom of the meniscus at eye level, and round to the nearest tenth of a milliliter.

Read the bottom of the meniscus at eye level; report your data to the nearest calibration mark and add an estimated digit.

26: What is the calorimeter constant? The amount of heat required to change the temperature of a constant-pressure calorimeter by 1oC. The amount of heat required to change the temperature of one mole of a constant-pressure calorimeter by 1oC. The amount of heat required to change the temperature of one gram of a constant-pressure calorimeter by 1oC. The amount of heat exchanged by a calorimeter at constant pressure. An insulated container used to measure the heat released or absorbed by the contents.

The amount of heat required to change the temperature of a constant-pressure calorimeter by 1oC.

16: If you combine an aqueous solution of your unknown mixture of cations with a reagent that should produce a precipitate with one of the cations involved in the experiment and you observe the formation of a precipitate, what should you conclude? The cation under consideration is present in the unknown mixture. Other cations are inhibiting the precipitation. The reagent must be contaminated and should be replaced. The cation under consideration is not present in the unknown mixture

The cation under consideration is present in the unknown mixture.

13: What is the definition of the molar enthalpy of neutralization? Type: Multiple Choice Points Awarded: 0/1 Your Answer(s): A measurement of the amount of heat absorbed or released by a neutralization reaction. Correct Answer(s): The amount of heat required to change the temperature of a neutral solution by 1oC. The amount of heat required to change the temperature of one mole of a neutral solution by 1oC. The amount of heat required to change the temperature of one gram of a neutral solution by 1oC. A measurement of the amount of heat absorbed or released by a neutralization reaction. The heat released in the neutralization of one mole of acid or base at constant pressure.

The heat released in the neutralization of one mole of acid or base at constant pressure.

24: A scientist does two sets of experiments with three trials each to determine the density of an unknown solution. The three trials for the first experiment have a standard deviation of 0.0137g/mL. The three trials for the second experiment have a standard deviation of 0.0980g/mL. What can we infer? The measurements from the first experiment were more accurate. The measurements from the first experiment were more precise. Rationale: Please refer to Appendix I in your lab manual. The measurements from the second experiment were more accurate. The measurements from the second experiment were more precise. a and b a and d c and d All of the above None of the above.

The measurements from the first experiment were more precise.

22: Which of the following are indications of an exothermic reaction? Check all that apply. The temperature of the solution increases. (correct) The temperature of the solution decreases. The system has more enthalpy than before the reaction occurred. The system has less enthalpy than before the reaction occurred. ΔH > 0 ΔH < 0 The reaction released heat to the surroundings. The reaction absorbed heat from the surroundings.

The system has less enthalpy than before the reaction occurred. (correct) ΔH < 0 (correct) The reaction released heat to the surroundings. (correct)

3: Which of the following is NOT proper attire for the lab (check all that apply): Sweat pants Tights Closed-toe shoes which leave the top of the foot exposed Long sleeved shirt with close-fitting sleeves Long hair that has been pinned back

Tights (correct) Closed-toe shoes which leave the top of the foot exposed (correct)

29: Why is wearing eye protection (full splash-proof goggles) at all times in this laboratory a requirement? Because the instructors think you look funny with them on. To protect your eyes from damage!

To protect your eyes from damage!

20: How should you report your reading from the buret? To three significant figures To the nearest mL To the nearest tenth of a mL To the nearest calibration mark, then add one estimated digit To four significant figures To the nearest calibration mark

To the nearest calibration mark, then add one estimated digit

17: What hazards are associated with the HCl(aq) being used in the Qualitative Analysis Experiment? Check all that apply. Toxic Corrosive Irritant to skin Irritant to respiratory tract Causes skin discoloration Carcinogen Oxidant

Toxic (correct) Corrosive (correct) Irritant to skin (correct) Irritant to respiratory tract (correct)

5: What hazards are associated with the silver nitrate being used in the Qualitative Analysis Experiment? Check all that apply. Toxic Corrosive Irritant to skin Irritant to respiratory tract Causes skin discoloration Oxidant Carcinogen

Toxic (correct) Irritant to skin (correct) Irritant to respiratory tract (correct)

11: Gloves worn in the chemistry lab must be latex-free. TRUE FALSE

True

21: A beaker that contains a chemical should be labeled with the name and concentration of that chemical. TRUE FALSE

True

24: A beaker that contains a chemical should be labeled with the name and concentration of that chemical. TRUE FALSE

True

28: A beaker that contains a chemical should be labeled with the name and concentration of that chemical. TRUE FALSE

True

30: If an instructor asks you what is in a beaker, you will be able to tell them the identity and concentration of the chemical in the beaker. TRUE False

True

15: Which graph are we NOT generating in this experiment? Temperature vs. Time Temperature vs. Volume pH vs. Time pH vs. Volume Volume NaOH added vs. pH Volume vs. Pressure Volume vs. 1/Pressure

Volume NaOH added vs. pH

27: How do we compensate for absorbance of light by the cuvet walls, the solvent, and the solutes other than the complex ion. We take it into account during our calculations after the data collection We calibrate with cuvet, solvent, and other solutes present We calibrate with just the complex present (but no cuvet, solvent or other solutes) We use cuvets and solvents that absorb at the same ? as the complex

We calibrate with cuvet, solvent, and other solutes present

30: What precautions should be taken when handling chemicals in the lab? Check all that apply. Wear approved splash-proof goggles at all times Wear approved non-latex gloves at all times Avoid skin contact Avoid inhalation Tie back long hair Wear appropriate lab attire

Wear approved splash-proof goggles at all times (correct) Wear approved non-latex gloves at all times (correct) Avoid skin contact (correct) Avoid inhalation (correct) Tie back long hair (correct) Wear appropriate lab attire (correct)

4: What precautions should be taken when handling chemicals in the lab? Check all that apply. Wear approved splash-proof goggles at all times Wear approved non-latex gloves at all times Avoid skin contact Avoid inhalation Tie back long hair Wear appropriate lab attire

Wear approved splash-proof goggles at all times (correct) Wear approved non-latex gloves at all times (correct) Avoid skin contact (correct) Avoid inhalation (correct) Tie back long hair (correct) Wear appropriate lab attire (correct)

12: Which is the final step when cleaning a piece of volumetric glassware, prior to making a measurement? Rinse with deionized water. Clean using a brush and approved laboratory glassware cleaner. Rinse with tap water. Wet the surfaces of the glassware with the liquid being measured.

Wet the surfaces of the glassware with the liquid being measured.

24: You have taken more acid than you need for your experiment. What is the proper step to take? You pour the acid back into the reagent bottle so as not to waste it. You pour the extra down the drain. You dispose of the extra chemical in the specified container and pour more carefully next time. You share the acid with another lab group so as not to waste it.

You dispose of the extra chemical in the specified container and pour more carefully next time.

8: You have taken more acid than you need for your experiment. What is the proper step to take? You pour the acid back into the reagent bottle so as not to waste it. You pour the extra down the drain. You dispose of the extra chemical in the specified container and pour more carefully next time. You share the acid with another lab group so as not to waste it.

You dispose of the extra chemical in the specified container and pour more carefully next time.

16: The correct procedure for transferring liquid with a volumetric pipet. First, rinse with tap water and do a second rinse with deionized water. If using an atomizer bulb: Compress the rubber bulb and place it carefully over the upper end of the pipet. The bulb only needs to cover the end of the pipet to create an airtight seal, there is no need to push the pipet farther into the bulb. You may want to lubricate the hole of the rubber bulb with a drop of deionized water. If using a rolling pipet top: Press the proper sized pipet top tightly onto the end of the pipet in order to create an airtight seal. Place the tip of the pipet in the liquid and draw the liquid into the pipet and above the calibration line. Keep the pipet tip submerged to avoid air bubble entry. Be careful not to draw the liquid into the bulb. Dispose of this first amount of liquid into a waste beaker. Once again, draw in the liquid to be measured above the calibration line in the pipet. If using an atomizer bulb: remove the bulb while simultaneously covering the tip of the pipet with your finger. Now allow the liquid level to drop to the required level by slowly allowing air to enter the pipet by a controlled lifting of the finger that is covering the end of the pipet. If using a rolling pipet top, there is no need to remove the top. Push the side button to allow your pipet to drain. When the liquid level is at the correct place, move the pipet tip to the glassware where you want the liquid delivered and release your finger. Allow the pipet to drain into the container and touch off any last drop on the pipet side of the glassware. There may be some liquid remaining in the pipet tip. Do no blow this remaining liquid from the pipet. The pipet was calibrated to deliver the correct volume with this liquid remaining. NEVER allow the liquid to enter the pipet top (atomizer bulb or rolling). What would you do if there was a tiny bit of liquid left inside the end of the pipet after the pipet has drained: You should blow through the pipet to drain this last drop so that your transfer will be accurate. You should touch any hanging drop of solution to the side of your beaker, but leave the small amount within the pipet. You should use a graduated cylinder instead, they're more precise than a volumetric pipet.

You should touch any hanging drop of solution to the side of your beaker, but leave the small amount within the pipet.

25: The correct procedure for transferring liquid with a volumetric pipet. First clean and rinse your pipet with tap water and do a second rinse with deionized water. If using an atomizer bulb: Compress the rubber bulb and place it carefully over the upper end of the pipet. The bulb only needs to cover the end of the pipet to create an airtight seal, there is no need to push the pipet farther into the bulb. You may want to lubricate the hole of the rubber bulb with a drop of deionized water. If using a rolling pipet top: Press the proper sized pipet top tightly onto the end of the pipet in order to create an airtight seal. Place the tip of the pipet in the liquid and draw the liquid into the pipet and above the calibration line. Keep the pipet tip submerged to avoid air bubble entry. Be careful not to draw the liquid into the bulb. Dispose of this first amount of liquid into a waste beaker. Once again, draw in the liquid to be measured above the calibration line in the pipet. If using an atomizer bulb: remove the bulb while simultaneously covering the tip of the pipet with your finger. Now allow the liquid level to drop to the required level by slowly allowing air to enter the pipet by a controlled lifting of the finger that is covering the end of the pipet. If using a rolling pipet top, there is no need to remove the top. Push the side button to allow your pipet to drain. When the liquid level is at the correct place, move the pipet tip to the glassware where you want the liquid delivered and release your finger. Allow the pipet to drain into the container and touch off any last drop on the pipet side of the glassware. There may be some liquid remaining in the pipet tip. Do no blow this remaining liquid from the pipet. The pipet was calibrated to deliver the correct volume with this liquid remaining. NEVER allow the liquid to enter the pipet top (atomizer bulb or rolling). What would you do if there was a tiny bit of liquid left inside the end of the pipet after the pipet has drained: You should blow through the pipet to drain this last drop so that your transfer will be accurate. You should touch any hanging drop of solution to the side of your beaker, but leave the small amount within the pipet. You should use a graduated cylinder instead, they're more precise than a volumetric pipet.

You should touch any hanging drop of solution to the side of your beaker, but leave the small amount within the pipet.

37: The correct procedure for transferring liquid with a volumetric pipet. 1. First clean and rinse your pipet with approved laboratory glassware cleaner, rinse with tap water and do a second rinse with deionized water. 2. Compress the rubber bulb and place it carefully over the upper end of the pipet. The bulb only needs to cover the end of the pipet to create an airtight seal, there is no need to push the pipet farther into the bulb. You may want to lubricate the hole of the rubber bulb with a drop of deionized water. 3. Place the tip of the pipet in the liquid and draw the liquid into the pipet and above the calibration line. Keep the pipet tip submerged to avoid air bubble entry. Be careful not to draw the liquid into the bulb. Dispose of this first amount of liquid into a waste beaker. 4. Once again, draw in the liquid to be measured above the calibration line in the pipet. Remove the bulb while simultaneously covering the tip of the pipet with your finger. Now allow the liquid level to drop to the required level by slowly allowing air to enter the pipet by a controlled lifting of the finger that is covering the end of the pipet. 5. When the liquid level is at the correct place, move the pipet tip to the glassware where you want the liquid delivered and release your finger. Allow the pipet to drain into the container and touch off any last drop on the pipet side of the glassware. 6. There may be some liquid remaining in the pipet tip. Do no blow this remaining liquid from the pipet. The pipet was calibrated to deliver the correct volume with this liquid remaining. There is a tiny bit of liquid left inside the end of the pipet after the pipet has drained: You should blow through the pipet to drain this last drop so that your transfer will be accurate. You should touch any hanging drop of solution to the side of your beaker, but leave the small amount within the pipet. You should use a graduated cylinder instead, they're more precise than a volumetric pipet.

You should touch any hanging drop of solution to the side of your beaker, but leave the small amount within the pipet.

12: The correct procedure for using a volumetric flask: 1. First clean and rinse your flask with tap water and do a second rinse with deionized water. 2. Using a properly sized volumetric pipet, deliver a measured amount of the standardized reagent solution to the volumetric flask. 3. Fill the flask to the graduation line with your solvent (it is helpful to use a disposable pipet to add the last few drops. If the solution is aqueous, the bottom of the meniscus should be at the graduation line. 4. If you overshoot the graduation line, you will need to remake your dilution. 5. Covering the top of the flask with a stopper or a piece of parafilm (and NOT your glove), mix the solution by inverting the flask several times. What do you do if you overshoot the graduation mark by adding too much solvent? Use a dropper to remove some solvent, this won't change the concentration of your dilution. You will have to remake the dilution.

You will have to remake the dilution.

22: Through the back-titration experiment, we are able to determine the effectiveness of antacids to neutralize stomach acid because: Dissolution in water and neutralization of antacids is not viable Antacids are weak bases that show buffer capacity The antacid tablet will dissolve completely in excess HCl a, b & c are true

a, b & c are true

19: What hazards are associated with the hydrochloric acid being used in the Intro to Lab Quest © Experiment? Toxic Corrosive Irritant to respiratory tract Carcinogen a and b a, b, and c a, b, and d all of the above

a,b,c

31: The correct procedure for using a volumetric flask: First clean and rinse your flask with approved laboratory glassware cleaner, rinse with tap water and do a second rinse with deionized water. Using a properly sized volumetric pipet, deliver a measured amount of the standardized reagent solution to the volumetric flask. Fill the flask to the graduation line with your solvent (it is helpful to use a disposable pipet to add the last few drops. If the solution is aqueous, the bottom of the meniscus should be at the graduation line. If you overshoot the graduation line, you will need to remake your dilution. Covering the top of the flask with a stopper or a piece of parafilm (and NOT your glove), mix the solution by inverting the flask several times. What do you use to cover your volumetric flask when mixing? Nothing if I'm extra careful. Parafilm A glove A glass stopper b & d

b & d

3: What role does the pH 3 buffer play in the vitamin C analysis? It precipitates proteins present in foods It prevents side reactions with sulfhydryl compounds and phenols It prevents the decomposition of vitamin c All of the above a and b a and c b and c

b and c

30: Which reagents are we using in this experiment? 1M NaOH 0.5M NaOH 0.2M NaOH 1M HCl 0.5M HCl 0.2M HCl Deionized Water pH indicatior b and e c and f b, e, g and h c, f, g and h b, e, g c, f, g a, e, g, h all of the reagents listed are being used in our experiment

c,f,g

1: Is this the correct procedure for cleaning glassware prior to making a measurement: First, Clean with approved laboratory glassware cleaner and a brush. Second, Rinse with tap water. Third, Rinse with deionized water from your wash bottle. Dispose of these rinses in your waste beaker. Yes No, there are steps missing.

yes

33: Is this the correct procedure for cleaning volumetric glassware prior to making a measurement: First, Rinse with tap water. Second, Rinse with deionized water from your wash bottle. Finally, if the glassware is volumetric, rinse once (or preferably twice) with the solution you are going to be measuring. Dispose of these rinses in your waste beaker. Yes No, there are steps missing.

yes