Environmental Impacts of the Automobile

Question 1

Environmental impacts due to automobiles are uniquely related to engineering design decisions that determine the release of pollutants.

Answer 1

False - land use decisions (construction of roads, parking lots) are also related.

Question 2

Improvements in fuel economy have lead to actual, measurable decreases in CO2 emissions.

Answer 2

True.

Question 3

What are the three (types of) gases emitted by automobiles, besides CO2?

Answer 3

Hydrocarbons (HC), nitrogen oxides (NO), and carbon monoxide (CO).

Question 4

Which of the 3 (types of) of non-CO2 gases emitted by automobiles lead to the formation of photochemical smog?

Answer 4

HC and NO gases.

Question 5

Name a chemical compound that falls under the umbrella of photochemical smog?

Answer 5

Ozone.

Question 6

Energy from what source causes HC and NO to react and form photochemical smog?

Answer 6

Heat from the sun.

Question 7

Which of the 3 (types of) non-CO2 gases emitted by automobiles is also known as a volatile organic compound (VOC)?

Answer 7

Hydrocarbons (HC).

Question 8

Although photochemical smog is made up of a number of chemical compounds, it is measured as an equivalent of which specific compound?

Answer 8

Ozone.

Question 9

When/why do automobiles emit CO and HC?

Answer 9

Due to the incomplete combustion of fuel.

Question 10

Hydrocarbons, when not the product of incomplete combustion, is emitted in what form?

Answer 10

As gasoline vapors.

Question 11

Where do HCs come from when in the form of gasoline vapor (3)?

Answer 11

Hot engines, from the venting of the engine crankcase, and from the venting/refilling of fuel tanks.

Question 12

Why do nitrogen oxides form during combustion?

Answer 12

Combustion supplies high temperatures that allow NOs to form by chemical reactions between nitrogen and oxygen in the air.

Question 13

In what type of areas does the automobile’s 3 non-CO2 air pollutants pose the most significant environmental problems?

Answer 13

Urban.

Question 14

Overall vehicle usage can be tracked by total vehicle-miles of travel (VMT) per year. How is VMT calculated for a given year?

Answer 14

(miles travelled per vehicle) X (total number of vehicles).

Question 15

Actual on-road emissions are generally higher than federal test cycle values.

Answer 15

True.

Question 16

Why are NO2 emissions underestimated by federal test cycle values?

Answer 16

Higher average speeds cause higher NO2 emissions.

Question 17

Why are overall emissions underestimated by federal test cycle values?

Answer 17

Improper maintenance or tampering with emission control systems.

Question 18

Why are HC & CO emissions underestimated by federal test cycle values?

Answer 18

Cogged air filters and dirty spark plugs.

Question 19

Why do light trucks (as opposed to regular cars) have increased environmental impact?

Answer 19

Heavier vehicles consume more gasoline and emit more CO2, HC, and NO, per mile of travel.

Question 20

What record percentage of the market did truck SUVs reach in model year 2021?

Answer 20

45%

Question 21

What record percentage of the market did pickup trucks reach in model year 2021?

Answer 21

16%

Question 22

What social phenomenon has offset the improvements made to each vehicle type’s fuel economy?

Answer 22

The trend away from sedans/wagons and towards truck SUVs & pickups.

Question 23

Currently, most motor vehicles worldwide are powered by what two forms of fuel?

Answer 23

Gasoline and diesel.

Question 24

Refined into gasoline, diesel oil, and jet fuel, petroleum supplies about what percentage of the energy used for all forms of transportation (in the US)?

Answer 24

90%

Question 25

Chemically, petroleum and its derivative fuels consist mainly of what two types of compounds?

Answer 25

Carbon and hydrogen compounds.

Question 26

Which gas is the natural product of combustion?

Answer 26

CO2

Question 27

Through what part of the car is CO2 released into the atmosphere?

Answer 27

Exhaust pipe.

Question 28

For every mole of octane, how many moles of CO2 and water vapor are produced?

Answer 28

8 moles of CO2, 9 moles of water vapor.

Question 29

What is the chemical formula for octane?

Answer 29

C8H18

Question 30

What programs have significantly alleviated the solid waste problems of discarded automobiles?

Answer 30

Recycling and reuse programs.

Question 31

How are non-recyclable car parts typically disposed?

Answer 31

Burial in a landfill.

Question 32

Today’s solid waste from automobiles reflects the materials used in cars that were manufactured an average of how long ago?

Answer 32

Eight to nine years ago.

Question 33

As the mix of materials used in auto
construction changes over time, the ability to reuse or recycle those materials also may change.

Answer 33

True.

Question 34

The environmental contaminants from automobiles can be categorized as either HC/NO/CO emissions or solid waste.

Answer 34

False - cars have and still emit lead and CFCs into the atmosphere.

Question 35

The population of older vehicles that use leaded gasoline constitutes the first largest source of U.S. lead emissions.

Answer 35

False - second largest, according to the EPA.

Question 36

Why do many non-US countries continue to use leaded gasoline?

Answer 36

Lower cost.

Question 37

How do automobiles emit CFCs?

Answer 37

Due to CFCs used in automotive air conditioners (pre-Montreal Protocol enforcement).

Question 38

Air conditioning systems in cars that utilize CFCs don’t necessarily emit them - how do they end up in the atmosphere?

Answer 38

Via leaks in the air conditioning system over the life of a car.

Question 39

Further production of CFCs has been phased out in the United States and other industrialized nations.

Answer 39

True.

Question 40

Generally, what is the last remaining (legal) source of CFCs?

Answer 40

Capture and recycling of the existing stock of CFCs will be the only source of these chemicals until they are finally depleted.

Question 41

What are the 4 methods by which to design cleaner cars?

Answer 41

Designing for energy efficiency, reducing pollutant formation, alternative fuels, and alternative vehicles.

Question 42

Why is the impact of CH4, N2O and CFCs so significant, if their emissions are small in comparison to CO2?

Answer 42

They have a higher global warming potential (GWP).

Question 43

What 5 parts of a car in particular have been redesigned to improve combustion efficiency and reduce NO formation?

Answer 43

Engine manifolds, cylinders, pistons, valves, and ignition system components.

Question 44

Besides modified forms of gasoline, name 4 alternative automobile fuels.

Answer 44

Diesel, methanol, ethanol, and compressed natural gas.

Question 45

Which alternative fuel is produced from biomass?

Answer 45

Ethanol.

Question 46

Alternative fuels promise to reduce what type of automotive emissions in particular?

Answer 46

Smog-forming automotive emissions.

Question 47

Name two types of alternative vehicles.

Answer 47

Electric and hybrid.

Question 48

Electric vehicles (EVs) have a battery instead of a gasoline tank, but still make use of an internal combustion engine.

Answer 48

False - they have an electric motor instead.

Question 49

Plug-in hybrid electric vehicles (PHEVs) have a battery, a gasoline tank, which both feed an internal combustion engine.

Answer 49

False - the battery feeds an electric motor.