Chem 1212 quiz questions

In a similar Exp. 9 experiment, a calibration plot of absorbance vs. concentration was obtained with the slope of the best-fit straight line as 1440 M-1. The diluted aspirin solution had an absorbance of 0.822. What is the concentration (M) of the aspirin in the dilute aspirin solution? To enter a number in scientific notation, use "e" to represent the "x 10" part of the number, followed by the exponent digits. For example, the number 1.23 x 10- 4 would be typed in as 1.23 e-4 Enter your answer with 3 significant figures.

0.000571

One tablet of generic aspirin was dissolved in 10 mL of 1.0 M NaOH and then diluted to 250 mL with deionized water. The sample was prepared by taking a 8.00 mL aliquot of this concentrated aspirin solution and diluting it to a final volume of 100.0 mL with FeCl3. A calibration plot determined that the diluted aspirin solution concentration was 5.907 x 10-4 M. What is the concentration (M) of the original aspirin solution? To enter a number in scientific notation, use "e" to represent the "x 10" part of the number, followed by the exponent digits. For example, the number 1.23 x 10- 4 would be typed in as 1.23 e-4 Enter your answer with 3 significant figures.

0.00738

What is the Molarity of the Ba(OH)2 solution if a 7.50 mL aliquot of the Ba(OH)2 solution required 14.6 mL of a 0.108 M H2SO4 solution to reach the equivalence point? Enter your numerical answer with 3 digits past the decimal.

0.210

Match the following definitions and examples. 1. The ratio of moles of solvent to total moles in solution a. P knot or vp knot b. colligative property c. vapor pressure d. mole fraction solvent 2. A property of a solution that is dependent on the number of solute molecules in solution. a. P knot or vp knot b. colligative property c. vapor pressure d. mole fraction solvent 3. The partial pressure of gas phase solvent molecules over a solution of pure solvent at a given temperature. a. P knot or vp knot b. colligative property c. vapor pressure d. mole fraction solvent

1. d 2. b 3. a

Ozzie wanted to do another experiment with a stronger H2O2 solution to check the accuracy of the experiment by calculating the theoretical volume of O2(g) it would produce. Then he could compare his experimental volume of O2(g) to the theoretical volume of O2(g). He used 5.20 mL of 3.18 M H2O2 and the partial pressure of O2 was 0.9959 atm and the temperature was 291.25 K. What volume of O2(g) could he theoretically produce (in mL)? Enter your answer to 3 significant figures.

198

Ozzie wanted to do another experiment using 15.5% (by mass) H2O2. What is the Molarity of this H2O2 solution ?

4.56 M H2O2

One tablet of generic aspirin was dissolved in 10 mL of 1.0 M NaOH and then diluted to a final volume of 125 mL with deionized water. A 2.50 mL aliquot of this concentrated aspirin solution was diluted to a final volume of 200 mL with FeCl3. From previous calculations by your partner, the dilute solution was found to be 2.94 x 10-4 M and the original, concentrated solution was determined to be 2.35 x 10-2 M. How many mg of aspirin are present in one tablet of the aspirin? Enter your answer with 3 significant figures.

530.2

A 0.0614 g sample of sodium salicylate was dissolved and diluted to a final volume of 100 mL with deionized water. What is the concentration of the sodium salicylate solution? Select one: a. 3.835 x 10-3 M b. 6.140 x 10-4 M c. 1.017 x 10-2 M d. 2.608 x 10-3 M

a

A calibration plot of absorbance vs. concentration was obtained with standard solutions of sodium salicylate, which had a slope of the best-fit straight line as 1240 M-1. The absorbance of a dilute aspirin solution mixed with FeCl3 was 0.91. What is the concentration of the dilute aspirin solution? Select one: a. 7.34 x 10-4 M b. 1.13 x 10-2 M c. 1.36 x 10-3 M d. 8.86 x 10-4 M

a

An 3.00 mL aliquot of 5.44 x 10-3 M sodium salicylate was diluted to a final volume of 750 mL with FeCl3 solution. What is the concentration of the dilute sodium salicylate solution? Select one: a. 2.18 x 10-5 M b. 1.36 x 10-3 M c. 1.22 x 10-4 M d. 4.14 x 10-4 M

a

For the procedural error, indicate if the error will affect the actual yield of [Ni(C2H8N2)3]Cl2 product and if it does, will it raise or lower the actual yield: Weighed the product while the product was still wet Select one: a. Raises the actual yield b. Lowers the actual yield c. No effect

a

For the procedural error, indicate if the error will affect the actual yield of copper(II) saccharinate product and if it does, will it raise or lower the actual yield: Scraping the filter paper so hard that small bits of filter paper are with the crystals on the watch glass Select one: a. Raises the actual yield b. No effect c. Lowers the actual yield

a

In the reaction below, classify the chemical species as the type of electrolyte. Ba(OH)2(aq) + H2SO4(aq) → BaSO4(s) + 2 H2O(ℓ) BaSO4 Select one: a. Nonelectrolyte b. Strong electrolyte c. Weak electrolyte

a

In this experiment, you will measure the temperature of the water, which is also the temperature of the gas that is captured in the graduated cylinder. Before doing calculations, the temperature must be converted to what unit of measure? Select one: a. Kelvin b. milliliter c. gram d. Celsius Check

a

Predict the conductivity of H2SO4, a strong acid. Select one: a. Strong electrolyte b. Nonelectrolyte c. Weak electrolyte

a

What is the conductivity classification for an unknown H that only partially ionizes in water? Select one: a. Weak electrolyte b. Strong electrolyte c. Nonelectrolyte

a

What is the mole to mole ratio between Cu(C2H3O2)2·H2O and NaC7H4SO3N·H2O? Select one: a. 1 mol Cu(C2H3O2)2·H2O : 2 mol NaC7H4SO3N·H2O b. 2 mol Cu(C2H3O2)2·H2O : 1 mol NaC7H4SO3N·H2O c. 1 mol Cu(C2H3O2)2·H2O : 1 mol NaC7H4SO3N·H2O d. 2 mol Cu(C2H3O2)2·H2O : 3 mol NaC7H4SO3N·H2O

a

What should you so if you spill NaOH on the lab bench? Select one: a. Clean the spill using a chemical absorbent pad from the chemical spill kit. b. Wash the lab bench for 15 minutes with solution from the eye wash station and notify the TA. c. Add H2SO4 to the spill to neutralize it and notify the TA. d. Leave the spill on the bench and let it evaporate.

a

What should you so if you spill NaOH on the lab bench? Select one: a. Clean the spill using a chemical absorbent pad from the chemical spill kit. Correct b. Wash the lab bench for 15 minutes with solution from the eye wash station and notify the TA. c. Add H2SO4 to the spill to neutralize it and notify the TA. d. Leave the spill on the bench and let it evaporate.

a

Which chemical(s) will be in the buret? Select one or more: a. NaOH b. H2O c. Fruit juice d. (C6H5OH)2C2O2C6H4 (phenolphthalein)

a

Which definition corresponds to an analyte? Select one: a. The chemical species of interest. b. The chemical species being added in a titration. c. A chemical species that has a pH value < 7.0 d. A chemical species that changes colors at different pH values.

a

Which statements explain the shape of the titration curve observed in lab? I. Initially, the conductivity is zero since the reaction has not begun. II. During the reaction, the conductivity decreases due to the increase of Ba+2 and OH- ions. III. At the equivalent point, the conductivity is nearly zero since all the Ba+2 and OH- ions have reacted to produce nonelectrolyte products. IV. After the endpoint, the conductivity increases due to the excess titrant. Select one or more: a. III and IV are TRUE. b. I & II are TRUE. c. I & III are TRUE. d. II & III are TRUE.

a

Zach and Nate used 2.45 g of Cu(C2H3O2)2·H2O and excess sodium saccharinate in their experiment. They recovered 4.27 g of Cu(C7H4SO3N)2(H2O)4·2 H2O. What is the percent yield? Select one: a. 65.0 % b. 57.4 % c. 63.4 % d. 65.7 % e. 72.6 %

a

Which of the following items of clothing are appropriate to wear in CHEM 1212 Lab to protect your skin ? Select all that apply. Select one or more: a. T-shirt b. Scrub pants c. Jeans d. Lab Apron e. Knee length shorts f. Leggings g. Tank top h. Midriff top

a, b, c, d

Which of the following items of clothing are appropriate to wear in CHEM 1212 Lab to protect your skin ? Select all that apply. Select one or more: a. T-shirt b. Scrub pants c. Jeans d. Lab Apron e. Knee length shorts f. Leggings g. Tank top h. Midriff top

a, b, c, d

Consider an experiment where 7.50 mL of an unknown H2O2(aq) solution reacted with the yeast at 22.3°C to produce 82.34 mL of gas. The barometric pressure was 764.8 torr. The vapor pressure of H2O is 19.8 torr at that temperature. Be sure to look at the units of the numbers when selecting your answers. a. What is the partial pressure of O2 (in atm) in the collected gas? b. How many moles of O2 were produced by the reaction? c. How many moles of H2O2 reacted to produce this amount of O2 ? d. What is the Molarity of the H2O2 solution? *END OF MIDTERM*

a. 0.9803 atm O2 b. 0.003329 mol O2 c. 0.006658 mol H2O2 d. 0.888 M H2O2

C6H8O6(aq) + C12H7O2NCl2(aq) → C6H6O6(aq) + C12H9O2NCl2(aq) a. Askor & Bich found that it required 14.81 mL of 1.07 x 10-3 M DCP solution to reach the endpoint when titrating a 6.00 mL aliquot of pear juice. Determine the following (to 3 significant figures): b. How many mL of this juice would Bich have to drink in order to meet the Daily Recommended Intake (DRI) ? c. How many mg of ascorbic acid, C6H8O6, are present in the juice aliquot ?

a. ? b. 194 c. 2.79

Nick and Kel reacted 3.10 g of NiCl2·6H2O with 11.50 mL of 4.00 M C2H8N2. At the end, the filtrate was a pale pink solution. The litmus test on the filtrate solution turned the red litmus paper to a blue color. They recovered 3.09 g of product, [Ni(C2H8N2)3 ] Cl2. Based on the experiment described, select the correct answers for the questions below. a. The chemical, C2H8N2, is the ... b. The theoretical yield is ... c. The chemical, NiCl2·6 H2O, is the ... d. The actual or experimental yield is ...

a. chemical present in excess b. 4.04 g c. limiting reagent d. 3.09 g

where does excess chemical go?

appropriate waste container

where does the reaction mixture go?

appropriate waste container

An experimental method to estimate the density of a crystal is to compare it to a variety of solution of known densities. Solution M (density = 0.65 g/mL), Solution N (density = 0.80 g/mL) and Solution W (density = 1.0 g/mL) are poured into a test tube. The liquids are immiscible with each other and solid S is insoluble in each. When a few crystals of S are added to the test tube, it sinks through solution M, but floats on top of solution N. What is the best approximate density of S? Select one: a. Density of S is greater than 0.80 g/mL but less than 1.0 g/mL. b. Density of S is greater than 0.65 g/mL but less than 0.80 g/mL. c. Density of S is greater than 1.0 g/mL. d. Density of S is less than 0.65 g/mL.

b

For the error, indicate if the error will affect the mg of citric acid present per mL of juice, and if it does, will it raise or lower the value of the mg citiric acid/ mL of juice? Diluting the NaOH solution before filling the buret Select one: a. No effect b. Raises the value of mg citric acid/mL juice c. Lowers the value of mg citric acid/mL juice

b

For the procedural error, indicate if the error will affect the actual yield of copper(II) saccharinate product and if it does, will it raise or lower the actual yield: Only leaving the beaker in the ice bath for 5 minutes instead of 25 minutes Select one: a. Raises the actual yield b. Lowers the actual yield c. No effect

b

In this reaction, you observed several different Cu species which had different physical attributes. Select the appropriate chemical formula(s) that corresponds to a sky blue solution. Select one or more: a. CuO b. Cu(OH)2 c. Cu d. CuSO4

b

Sal, Liz and Nate did the Determination of Aspirin experiment together since Liz's partner, Astrid was absent. Astrid took the data from the group and graphed the calibration data of the absorbances of the dilute sodium salicylate solutions versus the molarity of these solutions. Astrid's plot had a slope of 1750 M-1 while Sal, Liz & Nate's plots had a slope of 1680 M-1. Which statement(s) is/are TRUE about any effects the different slopes will have on the calculations of the concentration of the aspirin solutions? Select one or more: a. Multiplying by a larger dilute aspirin molarity will result in a larger concentrated aspirin molarity for Astrid. b. The molarity value of Astrid's concentrated aspirin solutions will be smaller than Liz's. c. There will not be any differences in the molarities since it is the same data. d. Astrid's molarity of the dilute aspirin solution will have a larger value than Sal's.

b

What is the density of a solid that weighs 3.78 g and occupies a volume of 4.55 mL? Select one: a. 0.770 g/mL b. 0.831 g/mL c. 1.20 g/mL d. 1.83 g/mL

b

What is the density of a solid that weighs 3.78 g and occupies a volume of 4.55 mL? Select one: a. 0.770 g/mL b. 0.831 g/mL c. 1.20 g/mL d. 1.83 g/mL

b

What is the vapor pressure (in kPa) of CH3OH, methanol, over a solution which is composed of 5.00 mL of methanol and 1.68 g of C6H5COOH, benzoic acid, at 25ºC? Pº methanol at 25ºC = 16.915 kPa Density of methanol is 0.792 g/mL Molar mass of benzoic acid is 122.12 g/mol Select one: a. 15.55 kPa b. 15.22 kPa c. 16.82 kPa d. 14.82 kPa

b

Which statement best explains what happens to the percent yield if the initial mass of Cu(C2H3O2)2·H2O (reactant) is less than its recorded mass due to forgetting to tare the weigh boat? Select one: a. The theoretical yield will be less since the calculations are based on the lesser amount. Since the theoretical yield is in the denominator, the percent yield will decrease. b. The theoretical yield will be greater since there is theoretically more reactant to form products. Since theoretical yield is in the denominator, the percent yield will decrease. c. The theoretical yield will be greater since there is theoretically more reactant to form products. Since theoretical yield is in the denominator, the percent yield will also increase. d. The theoretical yield will be less since the calculations are based on the lesser amount. Since the theoretical yield is in the denominator, the percent yield will increase.

b

Will use of a higher Molarity value of DCP affect the calculated mg of Vitamin C? Select one: a. Lowers the value of mg of Vitamin C b. Raises the value of mg of Vitamin C c. No effect

b

Which chemical(s) used in this experiment is/are toxic? Check all appropriate chemicals that apply. Select one or more: a. H2O2 b. NaOH c. H2SO4 d. Cu e. Zn

b, c

where does a cracked or chipped beaker go?

broken glass box

A common error in titration is over-titrating. Which of the following statement(s) is/are TRUE? Over-titrating means too much analyte was added to the reaction. Since the volume of titrant is too large, multiplying by a large number in the calculation of citric acid makes the mass of citric acid too high. Over-titrating in this reaction produces a dark pink (or peach) solution. Select one: a. I and II are TRUE. b. I and III are TRUE. c. II and III are TRUE. d. Only I is TRUE.

c

Cedrick & Astrid titrated a 10.00 mL aliquot of grapefruit juice with a 0.171 M NaOH solution to the end point. They calculated that there was 0.1698 g of citric acid present in the juice sample. What is the amount mg of citric acid present per mL of juice? Select one: a. 10.1 mg/mL b. 1.70 mg/mL c. 17.0 mg/mL d. 7.06 mg/mL

c

Cooper, Zach and Nate did this experiment dissolving 3.50 g of Cu(C2H3O2)2·H2O and adding 7.90 g NaC7H4SO3N·H2O. What is the theoretical yield of the product, Cu(C7H4SO3N)2(H2O)4· 2H2O(s) ? Select one: a. 11.40 g b. 9.48 g c. 9.39 g d. 9.62 g e. 9.63

c

For the procedural error, indicate if the error will affect the actual yield of [Ni(C2H8N2)3]Cl2 product and if it does, will it raise or lower the actual yield: Rinsing the product with 10 mL of acetone instead of 5 mL in step 11 Select one: a. Raises the actual yield b. Lowers the actual yield c. No effect

c

In the reaction below, classify each of the chemical species as the type of electrolyte. Ba(OH)2(aq) + H2SO4(aq) → BaSO4(s) + 2 H2O(ℓ) H2SO4 Select one: a. Weak electrolyte b. Nonelectrolyte c. Strong electrolyte

c

In today's experiment, which chemical species acts as the indicator? Select one: a. (HPO3)n (metaphosphoric acid) b. C6H8O6 (ascorbic acid or Vitamin C) c. C12H7O2NCl2 (2, 6-dichloroindophenol) d. pH 3 buffer

c

In today's experiment, which chemical species is the titrant? Select one: a. H2O b. H3C6H5O7 (citric acid) c. NaOH d. (C6H5OH)2C2O2C6H4 (phenolphthalein)

c

Piers & Aida performed this experiment together. However, when Piers did his calculations he forgot to subtract the vapor pressure of O2(g) while Aida did do this part of the calculations. Which of the following statement(s) are TRUE concerning Piers' calculations? I. Piers' calculations will still yield the same molarity of H2O2 as Aida. II. Piers' calculations will give a higher value of moles of H2O2(g) than Aida. III. Piers' calculations will give a higher partial pressure of O2(g) than Aida Select one: a. Only I is true. b. I & II are true. c. II and III are true. d. I and III are true.

c

Predict the conductivity of H3BO3, a weak acid. Select one: a. Nonelectrolyte b. Strong electrolyte c. Weak electrolyte

c

What color is the 2,6-dichloroindophenol solution initially? Select one: a. Colorless b. Pink c. Dark blue

c

What is the conductivity classification for an unknown C that dissolves completely in water and but doesn't dissociate into ions? Select one: a. Strong electrolyte b. Weak electrolyte c. Nonelectrolyte

c

What is the conductivity classification for an unknown F that dissolves completely in water and doesn't have any ions present in solution? Select one: a. Strong electrolyte b. Weak electrolyte c. Nonelectrolyte

c

Which definition corresponds to aliquot? Select one: a. The reactant that is completely consumed during the reaction. b. A chemical species that contains a metal ion that is coordinated to ligands. c. A small portion of a chemical species. d. The amount of product that could be produced using a given amount of reactant. e. The reactant that is present as extra material when the reaction is complete.

c

Which definition corresponds to limiting reagent? Select one: a. The reactant that is present as extra material when the reaction is complete. b. A small portion of a chemical species. The amount of product that could be produced using a given amount of reactant. c. The reactant that is completely consumed during the reaction. d. A chemical species that contains a metal ion that is coordinated to ligands.

c

Which of the following statements are TRUE if the standardization titration (Part II) was over-titrated? The molarity of DCP would be lowered since the volume of titrant is in the denominator of the calculation. Too much DCP was added in the titration, causing the Molarity of the ascorbic acid to be lowered. With a lower molarity of DCP, the amount of Vitamin C will also be lower even if the titrations in Part II were done correctly. Select one: a. Only I and II are TRUE. b. All (I, II, and III) are TRUE. c. Only II and III are TRUE. d. Only I and III are TRUE.

c

Will overtitrating the end point in Part III affect the value of mg of Vitamin C? Select one: a. Lowers the value of mg of Vitamin C b. No effect c. Raises the value of mg of Vitamin C

c

Adding water(ℓ) to diesel fuel (ℓ) results in two layers. What describes the relationship between diesel fuel and water? Select one: a. soluble b. insoluble c. miscible d. immiscible

d

Identify the reaction type for the generic reaction given. A + B → A+n + B-m Select one: a. Double Displacement b. Decomposition c. Combination d. Oxidation-Reduction e. Single Displacement

d

Identify the reaction type for the generic reaction given. A + B → AB Select one: a. Double Displacement b. Decomposition c. Single Displacement d. Combination e. Oxidation-Reduction

d

In this experiment, you will be using and measuring various chemical species by a variety of units. Which units of measure is used for the temperature of water? Select one: a. liter b. atmosphere c. grams d. Kelvin

d

In this experiment, you will be using and measuring various chemical species by a variety of units. Which units of measure is used for the volume of O2(g)? Select one: a. Kelvin b. torr c. grams d. milliliters

d

In this reaction, you observed several different Cu species which had different physical attributes. Select the appropriate chemical formula(s) that corresponds to a red-brown solid. Select one or more: a. CuO b. Cu(OH)2 c. CuSO4 d. Cu

d

What is the mole fraction (Χ) of CH3OH, methanol, in a solution of 8.00 mL of CH3OH and 8.05 g of C6H5COOH, benzoic acid ? Density of methanol is 0.792 g/mL Molar mass of CH3OH is 32.04 g/mol Molar mass of C6H5COOH is 122.12 g/mol Select one: a. 0.900 b. 0.800 c. 0.850 d. 0.750 e. 0.875

d

What should you do if NaOH gets into your eye because you took your googles off? Select one: a. Dry the skin around your eye with a chemical absorbent pad from the chemical spill kit. b. Use the gauze (from the first aid kit) to make a patch and place over your eye. c. Put your googles on and wash the rest of your face for 15 minutes with water. d. Wash your eye for 15 minutes with the solution from the eyewash station and notify the TA.

d

What will result when water (density = 1.0 g/mL), liquid M (density = 0.65 g/mL, immiscible with H2O), and liquid N (density = 0.80 g/mL, immiscible with M and H2O) are poured into test tube. Select one: a. Two layers will form in the test tube. Water is the top layer, a mixture of liquid N and liquid M is the bottom layer. b. Three layers will form in the test tube. Water is the top layer, liquid N is middle layer, and liquid M is the bottom layer. c. Two layers will form in the test tube. Water is the bottom layer, a mixture of liquid N and liquid M is the top layer. d. Three layers will form in the test tube. Water is the bottom layer, liquid M is middle layer, and liquid N is the top layer. e. Three layers will form in the test tube. Water is the bottom layer, liquid N is middle layer, and liquid M is the top layer.

d

When is it okay to remove your chemical splash proof goggles? Select one: a. When the goggles fog up b. When washing glassware c. When not working with acids or bases d. When everyone in the lab has put away all chemicals and glassware.

d

What color is expected for the product, [Ni(C2H8N2)3]Cl2 (s), if NiCl2·6 H2O is the limiting reagent? Select one: a. White b. Dark Purple c. Blue-green d. Pink-violet e. Dark Blue f. Lime green

e

Which definition corresponds to coordination compound? Select one: a. The amount of product that could be produced using a given amount of reactant. b. A small portion of a chemical species. c. The reactant that is completely consumed during the reaction. d. The reactant that is present as extra material when the reaction is complete. e. A chemical species that contains a metal ion that is coordinated to ligands.

e

Match each item to its proper disposal method. Answers be used more than once. i. appropriate waste container ii. trash can iii. reagent bottle or jar iv. broken glass box Excess chemical Reaction mixture Used filter paper Cracked or chipped beaker

excess chemical: appropriate waste container reaction mixture: appropriate waste container used filter paper: trash can cracked or chipped beaker: broken glass box

Vida & Mindy titrated a 10.00 mL aliquot of grapefruit juice to its endpoint and it used 14.87 mL of a 0.0981 M NaOH solution. H3C6H5O7(aq) + 3 NaOH(aq) → Na3C6H5O7(aq) + 3 H2O(l) How many grams of citric acid are present in their aliquot? a. 0.09342 g b. 0.0628 g c. 0.2803 g d. 18.85 mg/mL e. 9.34 mg/mL f. 6.28 mg/mL What is the milligrams of citric acid per mL of juice? a. 0.09342 g b. 0.0628 g c. 0.2803 g d. 18.85 mg/mL e. 9.34 mg/mL f. 6.28 mg/mL

grams of citric acid=A mg of citric acid per mL=E

C6H8O6(aq) + C12H7O2NCl2(aq) → C6H6O6(aq) + C12H9O2NCl2(aq) C12H7O2NCl2 is abbreviated as DCP Ace, Corby & Astrid dissolved 0.0531 g of C6H8O6 in a 50.0 mL volumetric flask and filled it with deionized water to the mark. What is the Molarity of this standard solution of C6H8O6 ? a. 6.03x10-3 M b. 6.95x10-4 M c. 1.03 mg d. 5.71 mg e. 15.9 mg f. 2.10x10-3 M g. 1.87x10-1 M h. 1.06x10-2 M A 5.00 mL aliquot of the standard C6H8O6 above required 14.38 mL of DCP to reach the endpoint. What is the Molarity of the DCP solution? a. 6.03x10-3 M b. 6.95x10-4 M c. 1.03 mg d. 5.71 mg e. 15.9 mg f. 2.10x10-3 M g. 1.87x10-1 M h. 1.06x10-2 M A 15.00 mL aliquot of pear juice required 15.47 mL of the same DCP solution (from above) to reach the end point. How many mg of C6H8O6 are present in the aliquot? a. 6.03x10-3 M b. 6.95x10-4 M c. 1.03 mg d. 5.71 mg e. 15.9 mg f. 2.10x10-3 M g. 1.87x10-1 M h. 1.06x10-2 M

molarity of the standard soln=A molarity of the DCP soln=F mg C6H8O6 present in aliquot=D

Ethyl, Ann & Ami reacted 3.50 g of NiCl2·6 H2O with 12.00 mL of 4.00 M C2H8N2. They recovered 2.31 g of product, (Ni(C2H8N2)3)Cl2. The theoretical yield of the product is... The percent yield of the product is...

theoretical yield=4.56 g percent yield=50.6%

In a similar experiment, Cooper, Zach & Nate started with 2.85 g of Cu(C2H3O2)2·H2O and 6.77 g of NaC7H4SO3N·H2O and obtained 6.17 g of Cu(C7H4SO3N)2(H2O)4·2H2O. The theoretical yield of the product is _____ The percent yield of the product is _____

theoretical yield=7.65 g percent yield=80.7%

where does used filter paper go?

trash can

In this problem, click on the correct answer above, then drag and drop it in the correct box. Cedrick & Astrid titrated a 15.00 mL aliquot of grapefruit juice with a 0.134 M NaOH solution to the end point. The initial buret reading was 1.04 mL and the final buret reading was 24.83 mL. H3C6H5O7(aq) + 3 NaOH(aq) → Na3C6H5O7(aq) + 3 H2O(l) What is the volume of NaOH titrated? a. 0.129 g b. 0.204 g c. 0.341 g d. 23.79 mL e. 0.213 g f. 25.87 mL g. 15.00 mL What is the mass of citric acid in the juice sample? a. 0.129 g b. 0.204 g c. 0.341 g d. 23.79 mL e. 0.213 g f. 25.87 mL g. 15.00 mL

volume of NAOH titrated=D mass of citric acid=B