Gen Chem 1 Lab Final

General guidelines for preventing accidents include:

A. follow all safety instructions carefully B. know where the safety equipment is C. never play tricks or indulge in horseplay in the chemical laboratory D. become familiar with the hazards of equipment to be used E. become familiar with the hazards of the chemicals to be used

chemical spills can be prevented by:

A. keeping laboratory items well away from the edge of your laboratory bench. B. measuring quantities of chemical according to the laboratory procedure and not taking excess chemicals. C. notifying your instructor if you observe obstructions in the aisles or walkways of the laboratory space. D. walking slowly and carefully in the laboratory. E. supporting the beaker or flask with one hand under the container if you need to transport samples or solutions from one part of the lab to another.

What terms are signal words found on a GHS label?

Danger and Warning

How will we measure the volume of hydrogen gas generated?

Determining the volume of water displaced by hydrogen gas

Systematic error can be eliminated by collecting many data points and averaging.

False

True or False: It is okay to wear safety glasses that have small gaps around the top, sides and bottom

False

True or False: Pouring from bigger containers is safer

False

True or False: You are permitted to bring food and drink into the lab as long as it's packaged and you don't eat or drink it while in the lab

False

True or False: a lab thermometer has to be shaken down like medical thermometers.

False

Required attire in the lab includes

Full coverage safety goggles, Long pants, Disposable gloves, Lab coat, Closed-toe shoe

analytical balances

Have greater precision than top-loading balances. Are in a glass enclosure to minimize the effect of air movement.

Which elements generally have positive electron affinities?

Noble gases

Which of the following is a chemical property? Check all that apply:

Reactivity with water

What does RAMP stand for?

Recognize hazards, Assess the risks of hazards, Minimize the risks of hazards, Prepare for emergencies

What does SDS stand for?

Safety Data Sheet

Why do we need to equalize the water levels after the reaction?

To equalize the pressure inside and outside the flask

You find a beaker filled with an unknown clear liquid on your desk, what should you do?

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

Proper lab attire: Feet must be completely covered, and no skin should be showing between the top of the shoe and the bottom of the skirt or pants. True/ False

True

True or False: A saturated solution contains undissolved solute at equilibrium.

True

True or False: All students working in the laboratory are responsible for planning and carrying out each experiment in a manner that will ensure a safe environment to everyone in the facility and with care for university property.

True

True or False: Before using a chemical, you must learn its properties and hazards.

True

True or False: If your gloves become contaminated, you should replace them immediately.

True

True or False: In general, smaller atoms are more electronegative.

True

True or False: You must read all procedures thoroughly before entering the lab.

True

True/ False: Full splash-proof goggles must be worn from the moment you start working in the lab till you leave

True

a small standard deviation indicates high precision

True

Every graph you prepare must show the following features:

Visible data points, Axes labels including units, Descriptive title, Your name and date, Appropriate scale

Would you expect a small piece of aluminum oxide to have the same density as a large piece?

Yes, I would; density is an intensive physical property.

If you come to class wearing shorts (short skirts) and flip flops...

You will need to change into closed-toe shoes and long pants, or you will not be permitted to perform the experiment.

What is a fume hood?

a lab device that allows us to experiment with volatile or noxious chemicals whiles isolating the vapors from the lab

Safety in the instructional lab is...

a shared responsibility

When a piece of sodium metal is dropped into a calorimeter filled with water, hydrogen gas evolves. The temperature of the mixture rises because...

an exothermic reaction occurs

The exceptions to the trend of ionization energy are due to...

an increase in shielding by electrons in different sublevels, Hund's rule

Erlenmeyer flasks

are not volumetric glassware

If you do not understand a part of a lab procedure, you should...

ask the instructor before proceeding

The electron-sea model describes metals as...

cations in a sea of valence electrons

Constant-pressure calorimetry is commonly carried out in a

coffee cup

If an endothermic reaction occurs in a calorimeter, the contents of the calorimeter is...

cool

Improper waste disposal can result in...

damage to the environment, adverse reactions leading to fires or explosions, legal issues for your institution

A gallium atom is slightly smaller than an aluminum atom due to...

effective shielding provided by electrons in the d sublevel

If the heat of a reaction is measured at constant pressure, it is equal to a change in

enthalpy

accidents often result from...

failure to use common sense, an indifferent attitude, failure to follow instructions, making mistakes

What is the best time to clean equipment and tools in the lab?

immediately after use

You must discard your lab coat...

in the regular trash

According to Charles' law, if the temperature of a gas increases, its volume...

increases and it is a direct relationship

In general, atomic radius __________ down a group and ___________ across a period from left to right.

increases, decreases

Across a period (from left to right), the nuclear charge __________ , and the number of electrons __________ .

increases, increases

What are possible ways for chemicals to enter the body?

ingestion, inhalation, absorption, injection

The effective nuclear charge

is smaller than the actual nuclear charge due to shielding provided by electrons.

Properties of metals

malleable, good thermal conductivity, high boiling points, good electrical conductivity

If a hot metal is dropped into a calorimeter filled with water, the q of the metal is... and the q of the water is...

negative, positive respectively

Which elements generally have highly negative electron affinities?

nonmetals (except noble gases)

If a lab fire erupts, immediately

notify your instructor

If you forget to remove bubbles from the tip of your buret, the volume of the titrant needed to reach the endpoint might be...

overestimated

What does SDS include about a chemical?

proper storage, proper disposal, identity, physical and chemical properties, physical health hazards and ingredients

What is not proper lab attire?

ripped jeans, short pants, cropped tops, tights

Filtration is useful for separating

solid from a liquid

Why do we use both the top-loading and the analytical balances in this experiment?

the analytical balance is used to measure the mass of Mg, while the top-loading balance is used to measure the mass of water displaced. B. We don't have enough top-loading balances.

In an acid- base titration, the end pint occurs when...

the indicator changes its color

In assignments and tests pertaining to the lecture, the calorimeter constant is used to calculate the heat absorbed by the calorimeter. In the laboratory,

we account for exchange of thermal energy with the calorimeter by extrapolation to the time of mixing.

What do we mean by waste minimization?

we do not return excess reagent to the reagent bottles, we only take the amounts of reagents necessary to complete the experiment, we dispose of proper waste containers, we try to us little reagent as possible

bromophenol blue is... in acidic solution and ... in basic solution

yellow, blue