Lab Safety Flash Cards

buret is measured to which nearest mL

0.01mL

Attributes of a well prepared graph:

1. drawn as large as possible. 2. numerical labels on axes. 3. a title. 4. small dots exactly at the postions of the data points. 5. labels on the axes with the units.

hared Pairs of electrons: SP

1/2(ER − VE)

Stoichiometry of NaOH to vinegar in the neutralization?

1:1

Choose a chemical in Lab 11 that has irratating vapors?

3 M HCl

Select the chemicals in this experiment that are listed as acidic or corrosive. (Select all that apply.)

3M HCl, and KMnO4

Which of the following is NOT true about a net ionic equation?

All ionic species in the reaction mixture are shown.

What should be done with the waste from the Acid-Base Studies experiment?

All solutions can be flushed down the sink with plenty of water.

In the experiment on Le Châtelier's Principle, why must one be very careful when handling concentrated hydrochloric acid (12 M HCl)?

Highly corrosive and can injure the eyes and skin. Its vapor is a respiratory irritant so it should be used in fume hood.

During Flame test tab, what are the two types of hazards?

Hydrochloric acid, corrosive solution. and open flame

The buret in this titration experiment should contain which of the following?

NaOH solution

When placing test tubes in the centrifuge, what are the best practices?

Never put stoppers or other items in the centrifuge with your tubes. place test tubes containing about the same volumes in opposite positions on the rotor

vinegar is listed as which of the following?

None of the above

If one spills hydrochloric acid what is the FIRST thing one should do?

Rinse them in running water.

The valve on the bottom of the burner controls what?

The gas flow

What is the hottest part of the 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 will be no waste material in this experiment.

what is used to dispense CaCl2 and NH4NO3

a spoon-type spatula

select which might give off highly irritating vapors

acetic acid, ammonia, and hydrochloric acid

which are corrosive?

acetic acid, ammonia, hydrochloric acid, sodium hydroxide

what produces hydrogen gas in this experiment

all of the reducing agents

What should be done with waste materials in the Qualitative Analysis experiment?

all wastes should be put in the container on the side shelf, during the experiment, waste should be kept in a beaker at the bench. After the beaker is emptied, it should be rinsed with a little water and the rinsing should be poured into the container.

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 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 needed to reach the end point, an overestimation of the number of moles of analyte present.

When operating the centrifuge, students should do the following;

centrifuge for approximately 30 seconds. Make sure that the lid is completely shut and the safety knob is turned to engage the switch

Sodium hydroxide (NaOH) is listed as which of the following?

corrosive

receiving beaker in titration should contain what solutions?

deionized water, vinegar, phenolphthalein

Lab 7, chemical solutions used are conisdered to be what?

dilute but corrosive

Lab 3, All of the solutions prepared in this experiment should be __?

discarded in the waste container on the bench

if any of these get in your eyes what is the proper response?

flush the affected area

What is done with the waste from flame test?

flushed down the sink with plenty of water

in Lab 7 what was the independent and dependent variable?

independent = volume, dependent =pressure

cations should not be ___

ingested

Why should silver nitrate be handled carefully?

it will cause dark spots on the skin where it made contact

what precautions should be taken with a hot plate

keep flammable materials away from it. remember that it will stay hot after its turned off.

How should accidents be prevented when working with the reactions that produce hydrogen gas, which is flammable?

keep reations away from ignition sources, and rinse metal before discarding it

your lab partner should do what after flushing your eyes?

notify lab instructor

when the procedure says "condition the graduated cylinder" what does this mean?

rinse with vinegar several times

Which tests will be performed on the cations in question in this experiment?

solubility in aqueous H2SO4 solubility in ammonia solution solubility in aqueous HCl

Because acid-base reactions are highly exothermic, which of the following should you NOT mix together?

solutions with concentrations greater than 0.1 M

what is true about the endpoint of the titration?

the amount of analyte equals the amount of titrant added. the solution will change to faint pink for at least 30 seconds .

what should be done with the waste from the titrations lab

they should be flushed down the sink with plenty of water

why should a minimum amount of water be used

to create the least amount of waste solution as possible

Why is it important to "wash" a precipitate with water?

to remove soluble ions to prevent false tests later in the experiment

Some cations are ____

toxic

if cations are spilled on the skin the area should be ___

washed well with soap

Which of the following techniques will be used in this experiment?

washing of precipitates, decantation of supernatant liquids from precipitates, centrifugation

when cleaning the wire between flame tests, most cleaning is accomplished when?

while rinsing the wire with acid.

what should be done to avoid exposure to the vapors

work with it under a hood and avoid inhaling vapors