ISAT 100 Exam 2

Layers of the atmosphere in order

1. Troposphere (where we live) 2. Stratosphere 3. Mesosphere 4. Thermosphere

A wave of electromagnetic radiation has a wavelength of 450 nm. Assume that the speed of light is 3.00 × 108 m/s.

This wave has a frequency of 3.00×10^8 / 4.5×10^−7 = 6.7 × 10^14 Hz. The wavelength is equal to 4.5 × 10^-7 m.

100 O3 molecules (upper limit) per billion molecules that make up the air

Troposphere

Sr charge in its ionic form

+2

What charge will the ion formed from barium have?

+2 (elements from group 2 tend to for cations with a +2 charge)

In the compound MgO, the Mg ion has a charge of _____, while the O ion has a charge of _____.

+2; -2

Cl charge in its ionic form

-1

S charge in its ionic form

-2

mass ratio of H

0.176

Combustion is a type of chemical reaction, a process whereby substances described as _______1_______ are transformed into different substances called ________2________.

1. reactants 2. products

describe the general characteristics of a covalent bond

A covalent bond involves the sharing of electrons between two atoms. Electrons in a covalent bond are common property to both atoms that make up the bond. A covalent bond involves the attraction between the nucleus of each atom and the electrons of the other.

How is molecular motion increased?

Adding heat through a temperature difference Absorbing energy

Atom

Basic unit of matter

Match each element with the correct number of valence electrons. C Be Ne F

C - 4 Be - 2 Ne - 8 F - 7

correctly describe the origin and uses of CFCs

CFCs are inert and nontoxic. CFCs are very chemically persistent molecules.

What is the name of the energy transfer process that is responsible for a typical room having warmer air near the ceiling and cooler air near the floor?

Convection

One unit used to measure ozone concentration is the _______________ unit, which is equivalent to 3 × 10^16 O3 molecules in a vertical column of air with a cross-section of 1 cm2.

Dobson

correctly describe ions

F- is an example of an anion. Ions are formed when atoms lose or gain electrons.

describe the correct format used to represent a chemical compound

In the formula of an ionic compound the cation is always placed first. The number of atoms/ions in the formula is indicated by a subscript.

Which of the following cities are megacities? (Select all that apply.) Moscow Boston Delhi Beijing Phoenix Sao Paulo Istanbul Chicago

Moscow Delhi Beijing Sao Paulo Istanbul

What are the three primary qualities that affect how much heat is needed to change the physical state of an object?

Nature of the object Starting temperature of the object Mass of the object

Structural formula

Representation of how atoms are arranged, omitting lone pairs of electrons

Lewis structure

Representation of how atoms are connected, including lone pairs of electrons

Chemical formula

Shows only types and ratios of atoms present

Element

Simple, pure substance made of atoms

Thermodynamics

This is the study of heat and its relationship to mechanical energy.

HCN

This molecule possesses one triple bond.

for groups 1-2 true/false: A metal loses enough electrons to attain the same number as its nearest noble gas.

True

covalent bond

attraction formed between atoms when they share electrons

The molecules in a ______ flow over each other, yet are held together with relatively strong forces.

liquid

one _____ of any substance contains Avogadro's number of particles.

mole

A molecule that always contains carbon and may contain hydrogen, oxygen, and nitrogen is called a(n) __________ compound

organic

Examples of a ______ include the transition of a liquid to a gas or a solid to a liquid.

phase change

Humans usually judge temperature with their senses in a ______ manner. Assume no instruments are used.

relative

sublimation

solid to a gas/vapor

Molecule

tightly bound group of atoms that maintain the identity of the substance

symbol and units for wavelength.

λ nm (nanometers)

The degradation of energy ______.

is irreversible

In general ozone (O3) is much _____ reactive than oxygen (O2).

more

What products may be formed when a hydrocarbon undergoes combustion? Select all that apply. CO2 CH4 CO O2 heat

CO2 CO heat

Which of the following elements will form a cation? Select all that apply. P Ca Rb F

Ca Rb

Which of the following formulas for ionic compounds are correct? Select all that apply. Mg2O Ca3N2 AgCl2 CaO

Ca3N2 CaO

What radicals are responsible for ozone depletion by CFCs

Cl ClO

In the compound CrCl3 _______.

Cl has a -1 charge Cr has a +3 charge

Which of the following is true regarding the latent heat of fusion during melting?

It is used to break molecular bonds.

The laws of thermodynamics are concerned with relationships between what?

Mechanical energy Work Heat

thermostat thermometer

Metals expand or contract in response to change.

What happens to molecular motion if an object either absorbs energy or heat?

Molecular motion increases.

the allotrope of oxygen whose bonds can be broken by UVB radiation.

O3 (ozone)

What characterizes a free radical?

One or more unpaired electrons

correctly describe how to draw a Lewis structure for a given molecule

The A-group number of a main-group element gives the number of valence electrons. Each line between two atoms represents two electrons. The Lewis structure includes only the valence electrons for the molecule.

Draw the Lewis structure for the covalent molecule CCl4

The Lewis structure of CCl4 contains four single bonds. The Lewis structure of CCl4 contains 12 lone pairs.

Match each indoor air pollutant correctly with its common source: Tobacco smoke = Paints and varnishes = Basements = Ventilation systems =

Tobacco smoke = Formaldehyde, benzene Paints and varnishes = VOCs Basements = Radon Ventilation systems = O3, NO2, SO2, CO

True/False: UV radiation with a wavelength of 300 nm is classified as UV-B radiation.

True

True/False: UV-A is the least damaging to the Earth's surface.

True

kelvin

Water freezes at 273 and boils at 373.

Replacing halogen atoms (such as Cl) in CFCs with hydrogen results in a(n) _____.

decrease in boiling point and a decrease in molar mass

Lewis structures are used to represent covalent compounds. Shared electron pairs are shown either as pairs of _______________ or lines and only _______________ electrons are shown.

dots; valence or outer

kilocalorie (kcal)

energy needed to raise temperature of 1 kg of water 1 degree Celsius

high quality energy

energy with high order and high coherence, can be easily converted to work

low quality energy

energy with less order and less coherence, is less able to do work

coherent motion

external energy of an object associated with work

The _____________ of a wave is the number of wave cycles per second.

frequency

The molecules in a ______ are held together with weak forces that allow them to move constantly and randomly.

gas

Liquids change to gases at relatively low temperatures because ______.

some of the liquid's molecules have high enough energy to escape into the surrounding atmosphere

ionic bond

the attraction between oppositely charged ions

molar mass of CCl4

154.0 g/mol

mass percent of H

17.6

The boiling of water occurs at 100°C, 212°F, and ______ K.

373

molar mass of SO2

64.1 g/mol

The temperature in Fahrenheit of a water sample that measures 25°C is

77 TF = 9/5 x Tc + 32°

Place the steps for drawing a Lewis structure in the correct order, starting with the first step at the top of the list.

1. count the number of outer electrons contributed to each atom 2. add the valence electrons contributed by each individual atom to determine the number of outer electrons for the species 3. arrange the outer electrons in pairs around the contributing atoms 4. ensure that each atom has a full outer shell

Which of the following can be attributed to the atmosphere of planet Earth?

The Earth's average temperature is higher than expected when considering its distance from the Sun.

Kinetic Molecular Theory

The collection of assumptions that all matter is made up of time atoms and molecules that interact physically, that explain the various states of matter, and that have an average kinetic energy that defines the temperature of a substance. Basic Premise: all matter is made of atoms

With molecules continuously moving between the liquid and gaseous states in both directions, what is the primary factor that determines whether evaporation or condensation is occurring?

The number of molecules either leaving or entering the liquid Reason: In evaporation, more molecules are leaving the liquid. In condensation, more molecules are returning to the liquid state.

Which of the following regions of the electromagnetic spectrum have sufficient energy to break covalent bonds? (Select all that apply.) X-ray Visible Radio waves Infrared Ultraviolet

X-ray Ultraviolet

Which of the following statements correctly describe the information gained from a balanced chemical equation? Select all that apply. a. Identities of substances involved b. Temperature at which the reaction is carried out c. Relative quantities of substances involved d. How fast a given reaction proceeds e. Often the physical states of reactants and products

a. Identities of substances involved e. Often the physical states of reactants and products c. Relative quantities of substances involved

Which of the following would correspond to types of radiation? (Select all that apply.) a. X-rays from an X-ray machine at the hospital b. Visible light from a candle c. The force holding two magnets together d. UV light from a black light

a. X-rays from an X-ray machine at the hospital b. Visible light from a candle d. UV light from a black light

Which of the following actions are permitted in balancing a chemical equation? a. Adding reactants or products b. Altering the formulas of reactants and products c. Multiplying all coefficients by a common factor d. Adding coefficients to formulas of reactants and products

c. Multiplying all coefficients by a common factor d. Adding coefficients to formulas of reactants and products

Compound

complex, pure substance made of atoms

The first law of thermodynamics can be summarized as follows: The heat energy supplied to a system, minus the work done by the system, is ______ the change in internal energy.

equal to

Gas molecules move faster/have a faster velocity at _________________ temperatures. Therefore, the temperature of a substance is a measure of the average kinetic energy of the molecules making up the substance.

higher

Traditional thermometers are based upon the idea that substances expand or contract at set rates due to changes in temperature, whereas modern thermometers measure the intensity of the _________________ radiation emitted from objects such as the human body.

infrared

plasmas are like gases but they can also...

interact strongly with magnetic fields conduct electricity

A chemical equation must be balanced. This means that the same _____ and _____ of atoms must appear on both sides of the equation.

number; type

reaction steps for a CFC molecule with stratospheric ozone

q. a CFC molecule is bombarded with UV light releasing a chlorine radical 2. chlorine radicals react with ozone to produce CIO and oxygen 3. CIOO decomposes to a chlorine radical and oxygen

describe how Roman numerals are used in naming and writing chemical formulas

A Roman numeral is included for any metal that can form more than one monatomic cation. The ion designated Fe(III) has a charge of +3.

Consider the Bohr model of an atom, in which electrons reside in energy levels, denoted as n, starting from nearby the nucleus (n = 1) to farther away from the nucleus (n = 3). Which of the following electronic transitions would result in the emission of light with the shortest wavelength? An electron moving from the n = ______ level to n = ______.

An electron moving from the n = 3 level to n = 1.

Describe an ionic compound

Compounds formed when metals combine with nonmetals. Compounds that contain no molecules.

describe the advantages and disadvantages of the replacements for CFCs

HFCs are considered greenhouse gases. HFCs are nontoxic and nonflammable.

Select the allotrope of oxygen whose bonds can be broken by UVB radiation. O O2 O3

O3

correctly describe molar mass

The molar mass of oxygen is 16.00 g/mol. This means that 1 mole of oxygen atoms has a mass of 16.00 g. The molar mass of a molecular substance is the mass per mole of its molecules. The periodic table can be used to calculate the molar mass of any substance.

True/False: UV-C radiation has the shortest wavelength.

True

Which of the following statements correctly describe a photon? Select all that apply. a. Matter cannot absorb or emit a fraction of a photon. b. A photon is a particle of electromagnetic radiation. c. A photon with a short wavelength has low energy. d. All photons have the same amount of energy.

a. Matter cannot absorb or emit a fraction of a photon. b. A photon is a particle of electromagnetic radiation.

Which of the following statements correctly describe the formation of ozone? Select all that apply. a. Ozone can be formed from O2. b. Ozone can only be formed synthetically. c. Once ozone is formed it persists in the atmosphere for a long period of time. d. Ozone is typically formed during a lightning storm.

a. Ozone can be formed from O2. d. Ozone is typically formed during a lightning storm.

Which of the following options correctly describe aerosols? Select all that apply. a. All aerosols are dangerous to human health. b. Aerosols can contribute to pollution. c. SO3 can combine with water to create sulfuric acid aerosols. d. Aerosols are liquid and solid particles that remain suspended in the air.

b. Aerosols can contribute to pollution. c. SO3 can combine with water to create sulfuric acid aerosols. d. Aerosols are liquid and solid particles that remain suspended in the air.

True or false: The phase change between a liquid and a solid occurs at different temperatures dependent upon the direction of the phase change; for example, the temperature of water freezing is different from the temperature of ice melting.

false, The direction of the phase change does not affect the temperature at which it occurs

Hydrocarbons are compounds that contain only _____ and _____.

hydrogen carbon

Introducing too many H atoms into a potential replacement for CFCs causes a(n) _____ in flammability and a(n) _____ in boiling point.

increase; decrease

Wavelength and frequency are _____ proportional to each other. As wavelength increases frequency will _____.

inversely; decrease

A catalyst ______.

is typically regenerated during the reaction undergoes no permanent change during a reaction

UV-C radiation has the highest energy of all the types of radiation but it is not biologically damaging because it never reaches the Earth. UV-C radiation is instead absorbed in the _____ by oxygen and _____.

stratosphere; ozone

Conduction is a transfer of energy that occurs ______.

through the interaction of molecules

Electrons that are found in the highest energy level are called ______________ electrons.

valence

In a heat pump, unlike a heat engine, ______.

work is used to cool a low-temperature region and heat a higher-temperature region

Which of the following are common units of concentration used when reporting the level of common air pollutants? Select all that apply. μg/(m^3) M % ppm ppb

μg/(m^3) ppm ppb

Al charge in its ionic form

+3

Which of the following options correctly describe each type of chemical compound? (Select all that apply.) -Molecular compounds tend to contain nonmetals only. -Nonmetals combine with metals to form ionic compounds. -Molecular compounds may contain ions. -Ionic compounds are composed of molecules. -Ionic compounds contain only one type of atom.

-Molecular compounds tend to contain nonmetals only. -Nonmetals combine with metals to form ionic compounds.

Which of the following options correctly interpret the information provided by the balanced equation CH4 + 2O2 → CO2 + 2H2O?

1 mole of CH4 produces 1 mole of CO2 when reacted with 2 moles of O2. 15 mol of CH4 will produce 15 mol of CO2 when burned completely in O2. 1 molecule of CH4 reacts with 2 molecules of O2

Place the steps taken to reduce the depletion of the ozone layer in chronological order, starting with the first step at the top of the list.

1. United Nations environmental program: world plan of action on the ozone layer 2. Vienna convention on the protection of the ozone layer 3. montreal protocol 4. complete stoppage of production of CFCs in developing nations

**A food Calorie is

1. the same thing as a kilocalorie. 2. equivalent to 1,000 calories. 3. a measure of the chemical energy released by the oxidation of food.

**While driving past a bank, you see that the Fahrenheit temperature reading is 16.9°. What is this reading on the Kelvin scale?

265 K

molar mass of PF3

88.0 g/mol

Atoms bond in order to fill their valence shell of electrons. Most elements strive for a total of _____ such electrons while hydrogen strives for a total of _____.

8; 2

glass bulb thermometer

A liquid expands in response to the highest reading.

Anion

A negatively charged ion (an ion with more electrons than its neutral atom)

Cation

A positively charges ion (an ion with fewer electrons than its neutral atom)

A single covalent bond is indicated by:

A single solid line

Reactants

A starting material in a chemical reaction

correctly describe a Lewis structure

Bonding electrons are shown as lines or pairs of dots between two atoms. Lone pairs are shown as pairs of dots on individual atoms.

Which of the following are considered air pollutants? Carbon monoxide Nitrogen Argon Nitrogen dioxide Particulate matter Water vapor Ozone

Carbon monoxide Nitrogen dioxide Particulate matter Ozone

In both the Celsius and Kelvin temperature scales, there exists 100 intervals between the freezing and boiling of water, while in the _____________ scale, there are 180 degrees between these two points.

Fahrenheit

True or false: For an electron to "jump" from a lower energy level to a higher one, energy must be emitted by the electron.

False: For an electron to move from a lower-energy to higher-energy state, energy must be absorbed, not emitted.

True or false: In order to balance the reaction of hydrogen gas (H2) with oxygen gas (O2) to form liquid H2O a student adds a subscript of 2 to the oxygen in H2O. This is an acceptable method of balancing the above reaction.

False: Subscripts of compounds involved in chemical reactions should never be changed because this changes the identity of the compound. Only coefficients should be added to balance chemical equations.

Which two types of molecules are potential replacements for CFCs?

HFCs hydrofluorocarbons. HCFCs hydrochlorofluorocarbons.

Heat engine

It can generate mechanical energy from the flow of heat from a hot area to a cold one.

Heat pump

It must use mechanical energy to move heat from a cold area to a hot one.

When considering the interaction of molecules, Cohesion is...

The attractive force between the same kind of molecules.

Consider the formula for the ionic compound Na2O. correctly interpret this formula

The cation in this compound is Na+. The compound contains 2 Na+ ions for every O2- ion.

correctly describe how to name an ionic compound

The cation is named first and the anion second. When naming the anionic portion of the ionic compound, the element name is changed to end in -ide.

**Why does a glass filled with a cold beverage seem to "sweat"?

The cold glass cools adjacent air to saturation, which is followed by condensation of water vapor.

Temperature

The measure of the average kinetic energy of the molecules of a substance

Which statement correctly describes the procedure used to predict the ion formed by nonmetal elements in Groups 15, 16, and 17?

The nonmetal gains enough electrons to attain the same number as its nearest noble gas.

correctly describe the mole

The number of particles in a mole is called Avogadro's number. One mole of any substance contains 6.02 x 1023 particles.

risk assessment

The process of evaluating scientific data and making predictions in an organized manner about the probabilities of an outcome.

**Why does a piece of metal feel cooler than a piece of wood at the same temperature?

You sense heat flowing from your body as cool, and metal is a better conductor than wood.

Temperature is based on the ______ molecular kinetic energy of a body.

average

Which of the following statements correctly describe a properly balanced chemical equation? Select all that apply. a. The mass of the reactants is not necessarily the same as the mass of the products. b. The total number of atoms of each element must be the same in the reactants and products. c. The physical states of the reactants may be different than the physical states of the products. d. The number of molecules in the reactants should be the same as the number of molecules in the products.

b. The total number of atoms of each element must be the same in the reactants and products. b. The physical states of the reactants may be different than the physical states of the products.

Which of the following statements correctly describes the sources and environmental effects of SO2 (sulfur dioxide)? Select all that apply. a. SO2 emissions have not decreased despite the Clean Air Act. b. SO2 is a form of particulate matter. c. SO2 can lead to the formation of aerosols. d. SO2 originates chiefly from burning fuel in car engines. e. SO2 can react with water to produce acid rain.

c. SO2 can lead to the formation of aerosols. e. SO2 can react with water to produce acid rain.

Organic compounds always contains the element _____.

carbon

A(n) _______________ is a substance that increases the rate of a reaction without being consumed. This type of substance is often used up but regenerated during the reaction.

catalyst

CFCs always contain ________.

chlorine fluorine carbon

True or false: A substance must be radioactive in order for it to emit radiation.

false

The heat involved in a solid-liquid phase change, that is, melting or freezing, is called the latent heat of

fusion

For the main-group elements (1, 2, etc.) the number of valence electrons for an element is equal to the ______ number for the element.

group

energy degradation occurs when...

high-quality energy is transformed to low-quality energy.

absolute zero

in a kelvin temperature scale. This is the point at which molecular motion ceases.

In a(n) _____ compound electrons are transferred from one atom or group of atoms to another. Conversely, in a(n) _____ compound electrons are shared.

ionic; covalent

It gets warmer when it rains because the phase transition of water vapor to rain releases heat. This type of heat is known as ______ heat.

latent

In the formation of ionic compounds a metal will ______ electrons and a nonmetal will ______ electrons to form an ion with the same number of electrons as the nearest ______ gas.

lose; gain; noble

In the formation of ionic compounds a metal will ______ electrons to form an ion with the same number of electrons as the nearest ______ gas.

lose; noble

Consider the balanced equation 2H2 + O2 → 2H2O. The coefficients (numbers in front of the formulas) correspond to the number of particles of each substance involved in the reaction, which is proportional to the _____ of each substance.

number of moles

A(n) ________________ pollutant is produced from chemical reactions involving one or more other pollutants.

secondary

True or false: After the completion of a chemical reaction the number of substances may change but the total mass of matter present remains constant.

true

The distance a wave travels during one cycle is called its ______________. This is usually measured as the distance between two _____________ or two troughs.

wavelength; peaks or crests

mass ratio of N

0.824

Heat occurs in two general ways:

1. The object obtains heat through a transfer from a second object with a higher temperature. 2. through energy-form conversions.

mass percent of N

82.4

Which human activity has the GREATEST net effect on atmospheric CO2 levels?

Burning fossil fuels

latent heat

The quantity of heat associated with a phase change

British thermal unit

The quantity of heat required to raise the temperature of one pound of water one degree Fahrenheit at a specified temperature. is used when describing appliances or energy consumption

conduction

The transfer of energy from one molecule to another

solid

a phase of matter that has a definite shape and volume these molecules are at regular distances from each other and are bound by relatively strong cohesive forces.

When naming an ionic compound, the _____ is always named first. To name the anion, the root of the nonmetal name is added to the suffix _____.

cation; -ide

incoherent motion

chaotic internal energy of an object associated with heating

A chemical equation is a statement using chemical _____1_______ that expresses both the identities and the relative ______2_______ of the reactants and products involved in a chemical or physical change.

1. formulas or symbols 2. quantity or proportions or moles

Which of the following human activities increase the levels of atmospheric CO2?

Burning fossil fuels Replacing trees with cultivated crops Respiration

During photosynthesis ________.

CO2 and H2O are consumed to produce stored glucose and sunlight is converted into stored chemical potential energy

12,000 O3 molecules (upper limit) per billion molecules that make up the air

Stratosphere

modern medical thermometer

They measure infrared radiation emitted from the body.

H2O2 (connectivity is HOOH)

This molecule possesses no multiple bonds.

CS2

This molecule possesses two double bonds.

Which of the following is the primary source of atmospheric sulfur dioxide (SO2)?

coal-burning power plants

A chemical equation that is properly balanced obeys the law of ______.

conservation of mass

In chemistry, the mole _______.

indicates amount of substance and is abbreviated mol

Chemists use the _____ as a unit of amount of substance.

mole

Electromagnetic radiation consists of particles called ________________, each of which has a discrete amount, or quantum, of energy. However, since electromagnetic radiation also has wave properties, each particle is also characterized by a specific _______________ and frequency.

photons; wavelength or energy

When considering the interaction of molecules, Adhesion is...

the attractive force between different kinds of molecules

Calorie

the energy needed to raise the temperature of 1 gram of water through 1 °C

Combustion

the process in which a substance burns in oxygen

entropy

the thermodynamic measure of disorder

Heat is a measurement of ______.

the total internal energy of the molecules of an object

external energy

the total potential and kinetic energy of an everyday-sized object

internal energy

the total potential and kinetic energy of the object's molecules.

True or false: All objects that you currently can see are emitting radiant energy.

true, Every object that has a temperature above absolute zero emits radiant energy.

A highly reactive species with one or more unpaired electrons is called a(n) _____.

free radical

Products

The elements or compounds produced by a chemical reaction.

correctly describe the greenhouse effect

The greenhouse effect causes the average temperature on Earth to be higher than predicted when considering its distance from the Sun. The greenhouse effect is a natural process. Atmospheric gases on Earth trap about 80% of the infrared radiation produced by the Earth, warming the planet.

correctly reflect the mass ratios and mass percentages of the elements in SO3

The mass percentage of O is 60.0%. The mass ratio of S is 0.400.

Radiation is a type of heat energy transfer that occurs between two objects ______.

as long as there is a temperature difference between the two

______ forces between molecules are termed cohesion and adhesion, depending on whether the force is between like or unlike molecules, respectively.

attractive

Which of the following options correctly describe the factors that affect air quality? (Select all that apply.) a. Geographical features of a region do not affect air quality. b. Weather patterns have an affect on air quality. c. The number of people living in a region affects air quality. d. The activities of people in neighboring regions do not have an effect on air quality.

b. Weather patterns have an affect on air quality. c. The number of people living in a region affects air quality. (Because Geographical features of a region DO affect air quality. and The activities of people in neighboring regions DO have an effect on air quality.)

Which of the following options correctly describe air pollutants? Select all that apply. a. Sulfur dioxide is the only gaseous air pollutant that is odorless. b. All air pollutants are gases. c. Some air pollutants are hazardous at levels well below 1 ppm. d. Particulate matter is an example of an air pollutant. e. Any substances other than nitrogen and oxygen are considered air pollutants.

c. Some air pollutants are hazardous at levels well below 1 ppm. d. Particulate matter is an example of an air pollutant.

A substance that participates in a chemical reaction but is regenerated so that it undergoes no permanent change is called a(n) ______.

catalyst

The bond formed between two nonmetals is called a(n) _____ bond. This bond involves the _____ of one or more electron pairs between the two atoms.

covalent; sharing