question

Which of these represents the best Lewis structure for acetylene (C 2 H 2 )?

answer

A. H-C-C-H (triple bond between C's)

question

Although carbon dioxide is the primary compound discussed with respect to global warming; of the common atmospheric components the global warming potential (GWP) of a carbon dioxide molecule is very low. Which statement best explains this pair of facts?

answer

C. CO 2 exists in relatively high concentrations.

question

How many atoms are present in 0.375 mol of palladium (Pd) atoms?

answer

C. 2.26 × 10^23

question

The greenhouse effect refers to the process by which

answer

C. atmospheric gases trap and return infrared radiation radiated by Earth.

question

Octane (C 8 H 18 ) is one of the principal components of gasoline. How many moles of CO 2 are produced during the combustion of 3.0 mol of octane? Unbalanced equation: C 8 H 18 + O 2 → CO 2 + H 2 O

answer

C. 24

question

The top graph shows the mean temperature over the past 160,000 years as determined from ice-core data. Which of graphs A through D best represents the carbon dioxide concentration in air over the same time period as measured from air bubbles trapped in the ice cores?

answer

C. Graph C

question

Hydrogen gas (H 2 ) is a promising alternative to fossil fuels. How many molecules are present in 1.0 kg of hydrogen gas?

answer

C. 3.0 × 10 26

question

What is the effect of infrared energy on matter?

answer

D. It increases the vibration of chemical bonds.

question

Which occurrences or processes are expected to reduce the level of atmospheric carbon? I. Decaying plant and animal remains II. The growth of trees III. Formation of carbonate rock in the ocean IV. Animal respiration

answer

B. II and III only

question

Although coal is a complex mixture of substances, its elemental composition can be approximated by the formula C 135 H 96 O 9 NS. Using this formula, predict the amount of CO 2 released from the combustion of 1.00 × 10 6 metric tons of coal (about the annual average for a coal-fired power plant). 1 metric ton = 1 × 10 3 kg

answer

B. 3.11 × 10 9 kg

question

The most abundant greenhouse gas in Earth's atmosphere is:

answer

B. H 2 O vapor

question

Identify the single most effective strategy to reduce carbon dioxide emissions.

answer

B. Develop alternate energy sources that do not rely on fossil fuels.

question

Tropospheric ozone (O 3 ) is a greenhouse gas. Why is O 3 not assigned a Global Warming Potential (GWP)?

answer

D. Ozone has a relatively short lifetime in the troposphere and its distribution is not uniform around the world.

question

Where is most of the carbon on earth stored?

answer

A. in the form of fossil fuels and carbonate minerals and rocks

question

Which substances are regulated by the Kyoto Protocol? I. argon II. carbon dioxide III. nitrogen IV. nitrous oxide V. sulfur hexafluoride

answer

C. II, IV, and V only

question

Land use changes have a big impact on global warming because of their effect on albedo. Albedo

answer

C. is the ratio of electromagnetic radiation reflected by a surface to the amount of radiation hitting that surface.

question

In order to make useful predictions, which factors must be accounted for by climatic models? I. Aerosol Emissions II. Land Use III. Solar Irradiance

answer

D. I, II, and III only

question

Which of the following has the lowest albedo?

answer

A. Ocean

question

The heat of combustion of methane, CH 4 , is 50.1 kJ/g. How much heat would be generated if 1.00 mol of methane undergoes complete combustion?

answer

D. 804 kJ

question

The energy that flows from a warmer body to a colder body is called

answer

A. heat.

question

The first law of thermodynamics states that

answer

D. energy is neither created nor destroyed.

question

The measure of how much energy is dispersed in a given process is called the

answer

A. entropy.

question

In which example is the entropy of the initial state lower than the entropy of the final state?

answer

A. A pot of water boils to produce water vapor at 100°C.

question

The following molecules contain only single bonds. NH 3 (g) + 3F 2 (g) → NF 3 (g) + 3 HF(g) The bond energies are: N H 391 kJ/mol; F F 158 kJ/mol; N F 272 kJ/mol; H F 566 kJ/mol. Which is the heat evolved or absorbed per mole of NH 3 that reacts with F 2 ?

answer

D. -867 kJ/mol

question

Which is not a known advantage of natural gas over other fossil fuels?

answer

C. It is far more abundant than any other fossil fuel.

question

During petroleum refining, catalysts play an extremely important role during the

answer

A. cracking and reforming processes.

question

The diagram below shows a simplified version of a fractionating column used in the petroleum industry. The compounds that are obtained at position D (bottom)

answer

A. asphalt.

question

Consider these three compounds. Which are isomers?

answer

B. I and III only

question

A gasoline's octane rating is a measure of the

answer

A. gasoline's resistance to causing knocking in a vehicle's engine.

question

A gasoline's octane rating is determined by

answer

A. comparing its burning properties to those of pure isooctane, which has an octane rating of 100.

question

Oxygenated gasolines are blends of petroleum-derived compounds with oxygen-containing compounds. Which of the following oxygenated compounds has been discontinued in some states because of potential health risks?

answer

C. MTBE

question

Over the very long run, the energy source that has the greatest potential to meet humanity's needs is

answer

D. solar (the sun).

question

Assume that an extremely inefficient electrical utility company delivers electrical energy to your home from a natural gas-burning power plant with an overall efficiency of only 31% and your furnace is 85% efficient in converting electrical energy into heat energy. What mass of natural gas the power plant must burn if heating your home requires 3.5 × 10 7 kJ? The heat of combustion of natural gas is 50.1 kJ/g.

answer

A. 2650 kg

question

Calculate the amount of energy that is saved by replacing a 75-watt incandescent light bulb with an 18-watt fluorescent bulb during the 1500-hour life of the incandescent bulb. One watt is the equivalent of one joule of energy used per second.

answer

A. 308,000 kJ

question

Power plants generate electricity by harnessing the energy stored in chemical bonds. Which lists, in the correct order, the forms that the energy takes to get from a fossil fuel to an electrical outlet?

answer

D. potential energy → heat energy → electrical energy → mechanical energy

question

Which of the following has the highest boiling point?

answer

B. Octane

question

scientists believe they know the average global temperature over the last 160,000 years. Which property of the ice core samples from Antartica provides this information?

answer

C. the 1H/2H ratio

question

which of the atmospheric components does not contribute to global warming?

answer

C. N2

question

Neither N2 or O2 are greenhouse gases because

answer

B. their overall electric charge distribution does not change when they vibrate

question

what international agreement attempted to reduce greenhouse gas emissions?

answer

A. Kyoto Protocol

question

Find the molar mass of ethano, C2H6O

answer

c. 46.07 g/mol

question

how many atoms are present in 0.375 mol of palladium (Pd) atoms?

answer

c. 2.26 x 10^23

question

scientists have correlated average global temperature with atmospheric carbon dioxide levels for the last 160,000 years using ice cores from Antartica. How is carbon dioxide level determined?

answer

a. by measuring the CO2 concentration in trapped air bubbles in the ice layers

question

which practices might be described as carbon sequestration? I. planting trees II. deforestation III. pumping carbon dioxide deep into the ocean

answer

d. I and III

question

what is the coefficient for oxygen in the balanced chemical equation for the combustion of heptane (C7H16) unbalanced equation = C2H16 + O2 → CO2 + H2O

answer

a. 11

question

which country has the highest per capita emission of carbon dioxide

answer

a. US

question

the history of average global temperature for the last 160,000 years is derived from isotopic analysis of ice layers in Antartica, Scientists study the ____ ratio in____

answer

b. 1H/2H, H20

question

argon, which compromises almost 1% of the atmosphere, is approximately 27 times more abundant than CO2, but does not contribute to global warming. Which explanation accounts for this fact?

answer

a. single atoms do not have bonds, therefore do not vibrate

question

calculate the percentage by mass of flourine in sulfur hexaflouride (SF6), a potent greenhouse gas

answer

c. 78%

question

the industrial revolution is a key point in the earth's atmospheric history because

answer

a. prior to that time large deposits of petroleum and coal were not being used as energy sources

question

calculate the percent of chlorine in CCl3F (Freon-11)

answer

a. 77.5%

question

identify the single most effective strategy to reduce carbon dioxide emissions

answer

d. develop alternate energy sources that do no rely on fossil fuels

question

the heat combustion of ethane, C2H6, is 1560 kJ,mol, what is heat of combustion of ethane in kJ per gram

answer

a. 51.9 kJ/g

question

the energy that flows from a warmer body to a colder body is called

answer

a. heat

question

the energy stored in the chemical bonds of fossil fuels is a form of ____ energy

answer

c. potential

question

the energy of motion is called ____ energy

answer

d. kinetic

question

the first law of thermodynamics states that

answer

d. energy is neither created or destroyed

question

based on this reaction and its energy profile CH4 (g) + 2O2 (g) → CO2 (g) + 2H2O (g)

answer

a. exothermic

question

how is heat energy used to generate electricity

answer

b. heat boils water to make steam, which drives a turbine

question

which is correct statement of the second law of thermodynamics

answer

a. entropy of the universe is constantly increasing

question

combustion is a chemical process in which a fuel combines with ____ to release energy and form products

answer

b. oxygen

question

consider the following equation that describes the complete combustion of propane, C3H8, the bond energies are C-H 416 kJ/mol; C-C 356 kJ/mol; O--O 498 kJ/mol; C--O 803 kJ/mol; H-O 467 kJ/mol. which is the total amount of energy required to break all of the bonds in propane

answer

c. 4040 kJ/mol

question

which factor did not play a major role in the formation of fossil fuels from plant matter a. high temperature b. high pressure c. an absence of CO2 d. an abundance of sunlight

answer

d. an abundance of sunlight

question

in the petroleum industry, what does a refinery do

answer

a. it separates crude oil into fractions consisting of compounds with similar boiling points

question

which is produced in the greatest amount from a barrel of petroleum

answer

b. gasoline

question

which of the following is not a "clean coal" technology already in use?

answer

d. sequestration, to capture and store CO2 before it is emitted into the atmosphere (gasification, coal washing, and wet scrubbing all are)

question

why is the mileage a vehicle gets less when burning E85 than 100% gasoline?

answer

c. ethanol has a lower heat of combustion

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