Chem102 Final
These questions concern waste disposal in the Solubility Rules lab.
-All of the solutions prepared in this experiment should be discarded in the waste container on the bench. -It is a good idea to have a labeled beaker in the work area to collect waste during the experiment. -A squeeze bottle of deionized water can be used to rinse the solutions into the beaker. -Use the minimum amount of water possible, to avoid creating a large volume of waste solution.
Bunsen burner precatutions
-Flammable liquids should never be heated with a Bunsen burner. -The burner must never be left unattended. -The substance being heated should never be pointed at people. -The area near the burner should be clear of paper and other flammables. -If the flame blows out, the gas must be turned off, because gas could accumulate and an explosion could occur. -The area above the burner must be clear before it is lit.
Proper attire for lab includes which of the following? (Select all that apply.)
-a shirt and pants that overlap about 6" in the middle to cover the torso -a shirt that covers the shoulders and extends about 6" below the waist -shoes that cover the heels and toes -pants that extend to the ankles
What should be done with waste materials in the Qualitative Analysis experiment? (Select all that apply.)
-during the experiment, wastes should be kept in a labeled beaker at the bench. -After the beaker is emptied, it should be rinsed with a little water, and the rinsings should be poured into the container. -All wastes should be put in the container on the side shelf.
A buret should be read to which nearest mL?
0.01
probe techniques
1.The pH probe will be need to be retrained each time to figure out what pH is associated with what. 2. When you are placing the probe in the test tubes you need to make sure you are not contaminating the test tubes. 3.It's important to rinse of the probe between solutions 4.it was important to re-check the pH probe with the buffer solutions after calibration to verify the accuracy of the calibration.
(b) What should be done with metal waste from Part A2 (Ranking Reducing Agents) of the experiment?
Before disposal, the metal should be rinsed with water if it has been in acid solution.Before disposal, the metal should be blotted on a paper towel to dry it.The metal should be placed in the container for waste metal.
If 12 M HCl (or anything really) is splashed onto the eyes or skin, what is the proper response?First, next
Flush the affected area with a lot of water.,Have your lab partner notify the instructor about the spill while you continue rinsing with water.
If one spills hydrochloric acid on one's hands, what is the FIRST thing one should do?
Rinse them in running water.
Why should the container for the metals from Part A2 (Ranking Reducing Agents) not be tightly capped?
Hydrogen gas could build pressure in it.
list techniques/observations for the bunsen burner
In the Bunsen Burner Lighting video, it is important to light the match prior to turning on the gas, in case the match does not initially light. -When first lighting the bunsen burner, turn the air valve to close it. Then the gas valve should be closed and back it off a full turn.-Make sure you twist the hose so that the base is firmly on the lab counter.-Do not wear gloves while lighting the match.- Strike the match first, and then push down and turn the gas on.- Before the bunsen burner is lighted, tie back long hair and roll up long flow-y sleeves
Why should silver nitrate be handled carefully? (Select all that apply.)
It will cause dark spots where it contacts the skin
Select the chemicals in this experiment that are listed as acidic or corrosive. (Select all that apply.) KMnO4 Mg(NO3)2 Pb(NO3)2 3 M HCl AgNO3 Zn(NO3)2 Cu(NO3)2
KMnO4 and 3 M HCl
Tips for titration equipement
Keep the pH probe wet at all times or it will drift from the calibrated values. When not being used for measurement, keep the probe in pH 7 buffer solution. Condition the buret and ensure that no air bubbles are in the tip. Condition the graduated cylinder with vinegar solution before using it meaning Rinse with vinegar solution several times.. Read graduated cylinder and buret volumes carefully from the lowest point of the liquid meniscus with the sample at eyelevel.
What should you do when filling a buret? (Select all that apply.) Make sure the stopcock is closed.Use a pipet to remove liquid from the top in the event of over-filling.Condition the buret first.Make sure there are no air bubbles left in the buret tip.Make sure the stopcock is open.Fill the buret and drain to exactly the zero mark, as this particular experiment involves volume entry into MicroLab.
Make sure the stopcock is closed.,Condition the buret first.Make sure there are no air bubbles left in the buret tip.Fill the buret and drain to exactly the zero mark, as this particular experiment involves volume entry into MicroLab.
What should be done with liquid waste from Part A2 (Ranking Reducing Agents) of the experiment?
The liquid waste can be flushed down the sink with water.
What should be done with the wastes from Part B (Half-cell Potentials) of the experiment?
The solutions should be rinsed into the waste container for redox solutions.The metal wires should be rinsed and returned to the set-up sheet to be used by the next lab section.
What should be done with the wastes in the Flame Test experiment? As well as with the At the end of the Equilibrium and Le Châtelier's Principle experiment......What should be done with all waste generated in the titrations lab?
They should be flushed down the sink with plenty of water.
What should be done with the wastes from Part A1 (Ranking Oxidizing Agents) of the experiment? There will be no waste in this experiment. They should be put in the container for oxidizing agents. The contents of the well plate should be rinsed into the labeled waste container. The waste solutions can be flushed down the sink.
They should be put in the container for oxidizing agents.The contents of the well plate should be rinsed into the labeled waste container.
What should be done to avoid exposure to the vapors?
Work with it under a hood and avoid inhaling the vapors.
Select all of the following which might give off highly irritating vapors. (Select all that apply.)acetic acid (HC2H3O2)ammonia (NH3)hydrochloric acid (HCl)sodium hydroxide (NaOH)water (H2O)
acetic acid (HC2H3O2)ammonia (NH3)hydrochloric acid (HCl)
a) Select all of the following that are listed as corrosive. (Select all that apply.) acetic acid (HC2H3O2)ammonia (NH3)hydrochloric acid (HCl)sodium hydroxide (NaOH)water (H2O)
acetic acid (HC2H3O2)ammonia (NH3)hydrochloric acid (HCl)sodium hydroxide (NaOH)
Twisting the sleeve to open the holes (baffles) above the base of the burner does which of the following?
allows more air (oxygen) into the flame
If you condition the receiver beaker with the analyte solution prior to adding the measured volume of analyte to be titrated, what is the effect?
an increase in the volume of the titrant required to reach the end pointan overestimation of the number of moles of analyte present
If you rinse your buret with deionized water, but do not condition with the titrant solution, what is the effect?
an increase in the volume of the titrant required to reach the end pointan overestimation of the number of moles of analyte present
In the lab, a student must wear safety glasses or goggles...
at all times. (also they will be provided)
(a) Sodium hydroxide (NaOH) is listed as which of the following? corrosive, irritating vapors, toxic if ingested, causes staining on skin, flammable,none listed
corrosive
Phenolphthalein is listed as which of the following?
corrosive, irritating vapors, toxic if ingested, causes staining on skin, flammable,none listed
2 g CaCl2 (s, anhydrous) ~2 g NH4NO3 (s) 1 mL 1 M NaOH (aq) 1 mL 1 M FeCl3 (aq) are all __________ and the best saftey practice is ___
dilute, but corrosive. They can attack the skin and cause permanent damage to the eyes. If any of the solutions splash into your eyes, flush them in the eyewash. Hold your eyes open or have someone assist you. If you spill any of the solutions on your skin or clothing, flush the area immediately with water. Have your lab partner notify your instructor about the accident.
Corrosive chemicals include
hydrochloric acid, 6 M HCl6 M H2SO46 M HNO3
Why is it important to re-check the pH probe? You should ________ the probe between solutions
it was important to re-check the pH probe with the buffer solutions after calibration to verify the accuracy of the calibration.If the measured pH of a buffer solution is more than 1.00 pH unit different than the given value of the solution, consider replacing that buffer solution and calibrating again.Rinse off probe between solutions.
Vinegar is listed as which of the following?corrosive, irritating vapors, toxic if ingested, causes staining on skin, flammable,none listed
none
Because acid-base reactions are highly exothermic, which of the following should you NOT mix together?
solutions with concentrations greater than 0.1 M
0.1 M Ag+ can cause
staining on the skin
hydrochloric acid (HCl) is corrosive and can cause injury to ____ and ______. It should be used in a ________________
the eyes and skin.Its vapor is a respiratory irritant, so it should be used in a fume hood.
The valve on the bottom of the burner controls which of the following?
the gas flow
What is the hottest part of a Bunsen burner flame?
the tip of the inner, dark blue cone
The wastes in the Molecular Modeling experiment should be disposed of in the following way.
there is no waste
When cleaning the wire between flame tests, most of the cleaning is accomplished when?
while rinsing the wire with acid