C3

During photosynthesis ________.

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

1 nm (nanometer) = _______.

10^-9 m

Which coefficients are needed to balance the simplified chemical equation representing the formation of ozone? energy + a O2→ b O3 a= and b=

3,2

True or false: Once the production of CFCs was halted there was a dramatic decrease in the amount of stratospheric chlorine

False

Which of the following factors cause an increase in ozone production? Select all that apply.

Sun closer to Earth, Sun directly overhead, Increased intensity of UV radiation

Select the correct symbol for frequency

v

Draw the Lewis structure for the covalent molecule CCl4. Which of the following statements correctly describes the Lewis structure of CCl4? Select all that apply.

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

Which of the following statements correctly describe a photon? Select all that apply.

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

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 by each atom. 2 - Add the valence electrons contributed by each individual atom to determine the total 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.

Place the reaction steps in order for the reaction of a CFC molecule with stratospheric ozone, starting with the first step at the top of the list.

1) CFC is bombarded with UV light releasing a chlorine radical 2) Chlorine radicals react with ozone to produce CIO and oxygen 3) Two CIO radicals combine to form CIOOCI 4)CIOOCI decomposes under UV radiation to CIOO and a chlorine radical 5) CIOO decomposes to a chlorine radial and oxygen

Rank the three types of UV radiation in order of increasing wavelength, starting with the shortest wavelength radiation at the top of the list.

1. UV-C 2. UV-B 3. UV-A

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 programme 2. Vienna convention on the protection of the ozone layer 3. montreal protocol 4. complete stoppage of production of CFC's in developing nations

Which of the following statements correctly describe natural variations in stratospheric ozone levels? Select all that apply

1. random fluctuations in ozone concentrations occur 2. The amount of radiation emitted by the sun varies over an 11 to 12 year cycle

Rank the following types of bonds from the longest to the shortest, starting with the longest bond at the top of the list.

1. single covalent bond 2. double covalent bond 3. triple covalent bond

Match each region of the atmosphere correctly with the abundance of ozone.

100 O3 - troposphere 12,000 03 - stratosphere

The danger of sunburn is greatest with the UV index is equal to ______.

15

Match each type of covalent bond correctly with the number of electrons shared between the bonding atoms

2 single 4 double 6 triple

A boron (B) atom has ____ valence electrons

3

The octet rule states that when atoms bond they may lose, gain, or share electrons in order to attain an outer level containing _______ electrons.

8

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

Match each type of formula with the correct representation.

A - Lewis structure B - Structural formula C - Chemical formula

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 = 3 level to n = 1.

Which of the following options correctly describes how H2O and N2O can cause ozone to break down in the stratosphere?

Both species form free radicals, which react with O3 to form O2.

Which of the following options is the correct Lewis structure for the molecule N2?

C

Match each element with the correct number of valence electrons

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

An organic compound that has the prefix hydro- (e.g., hydrocarbon) contains ________.

C-H bonds

Which of the following statements correctly describe the origin and uses of CFCs? Select all that apply

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

Match each type of formula with the correct description.

Chemical Formula - Shows only types and ratios of atoms present. 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

The most significant step toward halting the depletion of the ozone layer was the call to stop the production of _____.

Chlorofluorocarbons

Which of the following radicals are responsible for ozone depletion by CFCs? (Select all that apply.)

Ci, CIO

Which of the following are formed on polar stratospheric clouds in the Antarctic, causing severe ozone depletion when exposed to UV light?

Cl2 HOCl

Exposure to UVB radiation stimulates the production of vitamin _______.

D

One unit used to measure ozone concentration is the _________ unit, which is equivalent to 3 × 1016 O3 molecules in a vertical column of air with a cross-section of 1 cm2.

Dobson

The ______ unit is a means of measuring ozone concentration, which is based on the intensity of UV radiation through a column of air.

Dobson

Which of the following options correctly describe how to draw a Lewis structure for a given molecule? Select all that apply.

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

Which of the following statements correctly describe the general characteristics of a covalent bond? Select all that apply.

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. A covalent bond involves the sharing of electrons between two atoms.

Which of the following options correctly describe potential biological effects of UV radiation in addition to skin cancer? Select all that apply.

Exposure to UV radiation can cause retinal damage. Harmful UV radiation could have an effect on the carbon dioxide balance of our planet.

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

False

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.

Which of the following species cause ozone to break down naturally in the stratosphere? Select all that apply.

H2O, N2O

Match each molecule with the correct description of its bonding

H2O2 = the molecule posses no multiple bonds. HCN= this molecule possesses one triple bond. CS2= this molecule possesses two double bonds.

Which two types of molecules are potential replacements for CFCs?

HFCs and HCFCs

Which of the following statements describe the advantages and disadvantages of the replacements for CFCs? Select all that apply.

HFCs are considered greenhouse gases. HFCs are nontoxic and nonflammable

Which elements are found in HCFCs? Select all that apply.

Hydrogen Fluorine Carbon Chlorine

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

Increase, decrease

On average, the concentration of ozone _____ as one gets closer to either pole, with the exception being the seasonal ozone hole over the _____.

Increases; Antarctic

Which of the following statements correctly describe a Lewis structure? Select all that apply.

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

Place the layers of the atmosphere in the correct order, starting with the layer that is farthest from the Earth at the top of the list.

Mesosphere Stratosphere Troposphere

Dinitrogen monoxide (N2O) breaks down to form the nitrogen monoxide (NO) radical, which results in ozone depletion. Which of the following is a natural source for N2O?

Microorganisms in soil and water

Which of the following statements correctly describe the natural sources of chlorine? Select all that apply.

Natural sources of chlorine include seawater and volcanoes - HCl is a natural form of chlorine. - Natural chlorine-containing substances are water soluble

Which of the following radicals are responsible for ozone depletion? (Select all that apply.)

Nitrogen monoxide Hydroxyl

Does a sunscreen with an SPF of 100 block out twice as much harmful radiation as one with an SPF of 50? It is assumed that both sunscreens were applied in the same concentration on the skin.

No

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

O3

Which of the following statements correctly describe the formation of ozone? Select all that apply.

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

Which of the following statements correctly describe polar stratospheric clouds (PSCs)? Select all that apply

PSCs provide a surface for chemical reactions to occur. PSCs are composed of tiny ice crystals

Which color of visible light will have the lowest energy photons?

Red

Which of the following represents techniques that are currently used to quantify ozone levels in the atmosphere? (Select all that apply.)

Satellite-mounted detectors Weather balloons

The pair of electrons involved in a covalent bond is called a(n) ________ electron pair, whereas the electrons not involved in bonding are called an unshared or ________ pair.

Shared, Lone

Above which region of Earth is the largest ozone hole located?

South Pole

Why is the actual SPF of a sunscreen usually much lower than its reported value on the bottle?

Sunscreen is most always applied in a lower dosage than recommended.

Which of the following options correctly describe the UV Index? Select all that apply.

The UV Index is based on the length of time required for skin damage to occur. A UV Index color-coded yellow indicates a moderate level of UV radiation.

Which of the following statements correctly characterize the ozone layer? Select all that apply.

The actual concentration of O3 in the ozone layer is fairly small. The ozone layer filters UV light from the Sun.

Why is ozone depletion greater over the South Pole than the Arctic?

The air above the North Pole is not as cold, so that fewer polar stratospheric clouds form.

Which of the following options correctly describe the determination of ozone concentration by measuring UV radiation from the atmosphere? (Select all that apply.)

The lower the intensity of UV radiation reaching the detector, the greater the concentration of ozone in a column of air. Dobson units are used to quantify the amount of ozone in a column of air.

Which of the following statements correctly describes the consequences of halting the production of CFCs?

There has been a slow decrease in the concentration of stratospheric chlorine since the halt in production of CFCs.

Energy is quantized. What does this mean?

There is a basic unit of energy that cannot be subdivided further.

Why do natural sources of chlorine not cause as much harm to the ozone layer as CFCs?

They are lost to rainfall before reaching the stratosphere

Mineral-based sunblock preparations may contain _________.

TiO2 ZnO

Which of the following should be minimized for a suitable CFC replacement?

Toxicity

True or false: CFCs are inert, nontoxic compounds.

True

True or false: Sunscreens are transparent, whereas sunblocks are opaque.

True

Which of the following statements correctly describe the factors that influence the development of skin cancer in individuals?

UV-A is the form of UV radiation most strongly linked with skin cancers. - People with light-colored skin are more prone to melanoma

Which of the following options correctly describe the different types of UV radiation? Select all that apply.

UV-C - radiaiton has the shortest wavelength - UV-A is the least damaging to the Earths surface - UV radiation with a wavelength of 300 nm is classified as UV-B radiation

Match the type of radiant energy with the percentage of total energy emitted by the Sun.

Visible Radiation - 39% IR Radiation - 53% UV Radiation - 8%

Some UV radiation is beneficial to humans because UV-B light stimulates the production of _______, which is important for healthy bones and immune systems.

Vitamin D

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

Wavelength; crest

Which of the following options correctly describe the unique conditions in the Antarctic that cause the region to have a disproportionately large hole in the ozone layer?

Winds in the area form a vortex that prevents warmer air from entering the Antarctic. - Polar stratospheric clouds formed in this region initiate reactions of benign species to more reactive species. - Temperatures are as cold as -90 C

Which of the following regions of the electromagnetic spectrum have sufficient energy to break covalent bonds? (Select all that apply.)

X-ray and ultraviolet

Select the correct symbol and units for wavelength. More than one unit and/or symbol may be correct.

^ nm λ

Which of the following options correctly describe the determination of ozone concentration by measuring UV radiation from the atmosphere? (Select all that apply.)

a) Dobson units are used to quantify the amount of ozone in a column of air c) The lower the intensity of UV radiation reaching the detector, the greater the concentration of ozone in a column of air.

A nanometer is one _____ of a meter.

billionth

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

catalyst

Exposure to UVB radiation can cause damage to eye tissue, which can lead to _________, which are cloudy areas in the lens of the eye.

cataracts

CFCs always contain ________. (Select all that apply.)

chlorine fluorine carbon

Chlorofluorocarbons (CFCs) and their replacement compounds (HFCs and HCFCs) have a negative impact on our environment because they all _________.

contribute to global climate change

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

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

decrease in boiling point decrease in molar mass

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

decrease in boiling point 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

What were the most important properties considered when designing a suitable replacement for CFCs? Select all that apply.

extreme stability flammability toxicity

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

free radical

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

frequency

The speed of a wave is determined by multiplying the _______ of the wave by its wavelength. In a vacuum all electromagnetic radiation travels at a constant speed: ________ m/s.

frequency Blank 2: 3.00x10^8, 3 x 10^8, 300,000,000, 300000000, 3.00 x 10^8, 3x10^8, 3e8, 3.00e8, 3*10^8, or 3.00*10^8

Although HFCs are a good replacement for CFCs in terms of their physical properties and effect on the ozone layer, these compounds ___________.

greenhouse gases and play a role in global warming

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 and wavelength are related through the equation: E = hcλ

h matches ChoicePlanck's constant c matches Choicespeed of light E matches Choiceenergy per photon λ matches Choicewavelength

Match each prefix or term to its correct meaning when applied to an organic compound.

hydro-

Exposure to UV radiation causes the concentration of melanin in the skin to ______.

increase

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

inversely; decrease

Which of the following correctly describes skin cancer?

is caused by exposure to UVA and UVB radiation

A catalyst ______. (Select all that apply.)

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

On average, the concentration of stratospheric ozone at the equator is _____ than at the poles.

lower

Exposure to UV radiation causes an increase in the concentration of the skin pigment known as _________

melanin

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

more

What characterizes a free radical?

one or more unpaired electrons

A designated region in the stratosphere of maximum O3 concentration is called the _______ layer.

ozone

UV-C radiation is absorbed by which two substances in the stratosphere

ozone and oxygen

The process by which green plants convert sunlight into stored chemical potential energy by producing glucose and oxygen is called ______.

photosynthesis

What type of clouds are composed of tiny icy crystals formed from a small amount of water vapor present in a specific region of the atmosphere?

polar stratospheric clouds

A single covalent bond is indicated by:

single solid line

An example of a ________ state would be the concentration of ozone being replenished as fast as it is destroyed.

steady

What is the term used to describe a condition in which a dynamic system has no net change in concentration of the major species involved?

steady state

The maximum concentration of ozone in the atmosophere is found in the ________ .

stratosphere

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

Electrons that are found in the highest energy level are called ______ electrons

valence

Select the correct symbol and units for wavelength. More than one unit and/or symbol may be correct.

λ nm

Which of the following would correspond to types of radiation?

• X-rays from an X-ray machine at the hospital, • Visible light from a candle and • UV light from a black light are all types of radiation.

Which of the following is the correct Lewis structure for the molecule OF2?

the answer is whatever pic has for dots on O so like two on top and two on bottom of the o ö . . like this but closer

The region of the atmosphere closest to Earth is called the _____. The region of the atmosphere that contains the ozone layer is called the _____.

troposphere and stratosphere