CHE115L Final

How much aluminum will you use? (lab 5)

1.25g

If you need to measure 87.5 mL of a liquid, which piece of equipment from this list would be most precise?

100 mL Graduated Cylinder

In this lab, there are ........sets. You will work with.......bottles in each set. (lab 3)

4, 5

Convert 0.45 cm to mm.

4.5mm

What is the volume (in cm3) of a cuboid with side lengths of 3 cm, 5 cm, and 4 cm? (lab 2)

60cm^3

What information does not need to be included on a chemical waste label?

A description of the experiment the chemicals were used for

If you have a cuboid object with a mass of 27 g, and a length and width of 5.0 cm and 8.0 cm respectively, how thick would the object be in cm?

.675 cm

In general, water has a density of roughly

1 g/ml

In this experiment, we will be making waste aluminum into

Alum, a potential ingredient in deodorant

Which of the following instruments would give you the most precise mass of a small object?

Analytical Balance

Identify the types of information that are necessary to communicate with emergency responders.

Any chemicals involved in an incident, How the incident happened Any other hazards present in the lab

What was the identity of the ATX78757 gas?

CO2

A student removes a chemical sample from a reagent bottle to be used in an experiment. What should be done with any excess chemical remaining from this sample after the experiment is complete?

Check and see if anyone else can use the chemical. If not, discard in the proper waste container.

What are the best practices for safely handling waste in the lab?

Check labels or instructions before any disposal. Always wear appropriate Personal Protective Equipment.

Which signs are typically posted in areas of active lab work?

Chemical storage signs Safety equipment signs Personal protective equipment (PPE) sign Sign prohibiting food and drink

What should you do after finishing work with a reagent bottle?

Close the bottle. Return the bottle to its proper storage location.

While pulling an empty beaker off the shelf at the beginning of lab, it slips out of your hand onto the floor.

Closed-toe shoes

How should you prepare a buret for titration before loading it with titrant?

Condition the buret with titrant solution.

Identify the precautions to take with exits in the lab.

Do not block a door with an EXIT sign, Locate the exits prior to the start of lab.

Determine what supplies are provided and those that are not. (lab 3)

Droppers-provided Thermometer-provided Spot-plate-provided Funnel-not provided Buret-not provided

What assumption was made for this experiment? Lab 6

Fingerprints would not affect the mass of the flask

Which of the following safety equipment is in the lab?

Fire extinguisher Eye wash Safety shower Spill supplies

Identify the step that is not recommended when responding to an emergency.

Gather your belongings.

Determine the safest option in the lab if you need your vision to be corrected.

Wear corrective glasses or lenses under your safety goggles for the whole experiment, but always check with your TA or Instructor for your school's policy

What precautions should you take if you are using chemicals with this symbol? (Lab 1)

Wear safety goggles Wear gloves Keep away from heat and flames

Determine when you should remove your goggles in the lab room.

When everyone in the room is done handling any chemicals or glassware

What was the unit of pressure in the density of the air equation (dair = 0.3535 (P/T)? (lab 6)

atm

Which reaction is occurring in the test tube? (lab 3)

KCl(aq)+AgNO3(aq)⟶AgCl(s)+KNO3(aq)KCl(aq)+AgNO3(aq)⟶AgCl(s)+KNO3(aq)

While transferring a solution from a flask to a beaker, the solution accidentally spills down the front of the lab bench.

Lab coat

How was the mass of air determined?

Mass = (density x volume)

It is often helpful to remember the acronym PASS when using a fire extinguisher. Fill in the word that corresponds with each letter to complete the steps needed for operation of this device.

P: Pull the pin. A: Aim the nozzle at the base of the fire. S: Squeeze the lever slowly. S: Sweep the spray from side to side over the fire.

How can you improve your ability to see the indicator color change at the endpoint of a titration?

Place a piece of white paper under the analyte flask throughout the titration.

What is the first step for response to an emergency situation?

Remain calm and quiet, gather information, and assess the situation.

What's the best course of action to take if you get acid or base on your skin? lab 4

Rinse it off with water

Your goal is to separate two solids by adding water and then filtering the mixture. What are the final steps of ending up with two separate solids?

Scrape the solid off the filter paper into one container and evaporate the water from the filtrate to isolate the other solid.

What visible signs indicate a precipitation reaction when two solutions are mixed?

Solid settling out in the test tube A hazy or cloudy appearance

Which steps are necessary for cleaning a spill involving broken glass?

Stop the spread of the spill. Soak up any spilled liquid with absorbent material. Pick up large pieces of glass with gloved hands.

Determine which of the following statements is true.

Students are not permitted, at any time, to work alone in lab.

Why do you need to support a vacuum filtration apparatus with a clamp? (lab 5)

The filter funnel makes the apparatus top-heavy.

You can separate a mixture of sand and copper(II) sulfate pentahydrate using filtration. What difference in properties enables the separation of the two solids by filtration?

The hydrate is soluble in water but the sand is not.

What is the main precaution to take if a Gas Cylinder sign is present in the lab?

Visually check that the gas cylinder is restrained but keep a safe distance from it.

Which type of glassware can only be used to measure one volume, but does so with the highest precision? (lab 2)

Volumetric flask

In this experiment, we will observe (lab 3)

chemical reactions arising from mixing solutions

Identify the equipment best suited for extinguishing each type of fire.

clothing fire, fire blanket small benchtop fire, overturned beaker, large fire on floor, fire extinguisher

Approximately 1.25 ______ of solvent should be placed in a beaker in this procedure. (lab 1)

cm

When using acids and bases, note that these substances are

corrosive

qualitative

determining the chemical identity of an unknown sample.

chemical in eyes

eyewash station

Beverages are allowed in lab as long as they are in containers with lids.

false

Chewing gum is okay in the lab as long as you don't blow bubbles.

false

fire on person

fire blanket

Large fire on the benchtop

fire extinguisher

cuts or minor burns

first aid kit

While picking up a buret, an unknown solution left by a previous solution drips onto your hand.

gloves

While checking on a stirring solution, the solution splashes up towards your face.

goggles

Which of the following instruments is used to measure volume in lab 2?

graduated cylinder

Changing gloves often will minimize the spread of chemicals. To properly remove gloves, first,...., and then,...... Then insert, .......between the interior edge of the second glove and the skin, and remove the second glove.

grasp the exterior of one glove with a gloved hand, peel off the first glove, a bare finger

Be sure to wipe up any spills

immediately

Which of the following must not be placed in the flask when the ATX78757 ice is present because it could result in an explosion?

Tight-fitting stopper

In lab, you may need to evaluate the odor or smell of a chemical. What is the best way to smell a chemical sample?

Use your hand to gently waft the smell toward you.

What is the last step of any spill cleanup procedure?

Wipe down the affected area with detergent and water.

An indicator is a substance added to a sample that has......change, in response to the.......change, such as a.....of the sample.

a visible, color, chemical composition

In the density formula, d = mv, which of these is NOT accurate?

m=milliliters

Assuming the gas is either carbon dioxide, , or methane,, how many grams, will you need to fill a 250 mL flask? Even though these are not accurate, assume the following: (Lab 6)

mass of gass is 0.4479 g or 0.1631

Which concentrations will be you determining in lab? Lab 4

molarity and mass percent

To determine the efficiency of your process, you will be determining the....at the end of the expiremnt. To optimize your yield, you will preform all of the steps of the expiment...time

percent yield, 2-3

The indicator used in this experiment is (lab 4)

phenolphthalein

Phenolphthalein turns what color in basic

pink

In the first step of this experiment, you will react aluminum with... to dissolve the aluminum. Gently....this mixture will speed up the reaction. (lab 5)

potassium hydroxide, heating

Determining the amount of a sample or the amounts of each chemical component within a sample is

quantitiative

chemicals on clothes

safety shower

The technique used today is a type of ____________ method. (lab 1)

separation

According to the scenario, who is asking you to perform this work?

the National Aeronautics and Space Administration (NASA)

In this experiment we will be measuring the molar mass using ____________. (lab 6)

the gas laws

Which value was not experimentally determined and needed to be calculated?

the mass of 'earth air' in the flask

Make every effort to avoid contact with

the skin and lab surfaces

What experimental method will you be using in this lab? (lab 4)

titration

In this method, the sample will migrate toward the ______of the paper (Lab 1)

top

Food items should not be brought into the lab.

true

Tobacco products of all kinds are prohibited in lab.

true

The solvents that you will use consist of ____________. (lab 1)

water, ethanol

What color was the ATX78757 ice?

white