Module 2

Question 1

1a. define: humidity

Answer 1

the moisture content of air

Question 2

1b. define: absolute humidity

Answer 2

the mass water vapor contained in a certain volume of air

Question 3

1c. define: relative humidity

Answer 3

The ratio of the mass of water vapor In the air at a given temp to the maximum mass of water vapor the air could hold at that temp, expressed as a percentage.

Question 4

1d. define: greenhouse effect

Answer 4

The process by which certain gases (principally water vapor, carbon dioxide, and methane) trap heat that radiates from the earth

Question 5

1e. define: parts per million

Answer 5

The number of molecules (or atoms) of a substance in a mixture for every 1 million molecules (or atoms) in that mixture

Question 6

2. The temp is the same at 1 pm on two consecutive days. For a person who is outside working, however, the second ah feels cooler that the first day. On which day was the relative humidity higher?

Answer 6

the humidity is higher on the first day

Question 7

3. A child decides to keep his goldfish outside in a small bowl. He has to add water every day to keep the bowl full. On two consecutive days, the temps are very similar, but on the first day, the relative humidity is 90%, while the second day is 60%. On which day will the child add more water to the bowl?

Answer 7

the second day

Question 8

4. If you put a glass of water outside when the relative humidity outside is 100%, how quickly will the water evaporate?

Answer 8

the water will not evaporate

Question 9

5. Why does sweating cool people down?

Answer 9

Sweat cools you down because when it evaporates, it takes energy from your skin.

Question 10

6. What is the percentage of nitrogen in the air? What about oxygen?

Answer 10

Dry air is 78% nitrogen and 21% oxygen.

Question 11

7. What would be the consequence of removing all the carbon dioxide in earths air supply?

Answer 11

If the air had no carbon dioxide in it, the earth would be cooler (or plants would die of starvation)

Question 12

8. What would be the consequence of removing all the ozone in earths air supply?

Answer 12

Ultra violet light would kill a lot of living things

Question 13

9. What would be the consequence of a sudden increase in the concentration of oxygen in earth’s air supply?

Answer 13

If more oxygen were in the air, living things would not be as healthy and forest fires would increase in frequency and ferocity.

Question 14

10. Suppose astronomers found another solar system in which here was a sun just like our sun. Suppose further that a planet in this new solar system was just as far from its sun as is earth from our sun. Since the vast majority of energy that planets get comes from their suns, is it reasonable to assume that the new planet would have roughly the same average temp as that of earth? why or why not?

Answer 14

There is no reason to expect that the new planet will have the same temp as earth. If it does not have essentially the same air, with all the same levels of all the greenhouse gases, it will not have the same temperature.

Question 15

11. What makes up the majority of the air we exhale?

Answer 15

Nitrogen makes up the majority of air we exhale.

Question 16

12. Do we exhale more carbon dioxide or more oxygen?

Answer 16

We exhale more oxygen.

Question 17

13. Do the date indicate any significant global warming?

Answer 17

no

Question 18

14. The current concentration of ground-level ozone in the air is about 0.110ppm. What is that is percent?

Answer 18

0.0000110%

Question 19

15. Suppose you had a sample of air in which the concentration of nitrogen oxides is 0.023%. What would the concentration of nitrogen oxides be if you expressed it in ppm?

Answer 19

230 ppm

Question 20

16. Is the air cleaner today, or was it cleaner 30 years ago.

Answer 20

The air is much cleaner today than 30 years ago.

Question 21

17. What is the cost/benefit analysis?

Answer 21

A cost/benefit analysis attempts to determine whether or not to take an action by determining the benefits of that action as well as the costs.

Question 22

18. What does a catalytic converter do in a car?

Answer 22

A catalytic converter converts carbon monoxide in the car’s exhaust to carbon dioxide.

Question 23

19. What does a scrubber do in a smokestack?

Answer 23

A scrubber traps sulfur oxides in a smokestack and keeps them from being emitted into the air.

Question 24

20. In the US, many regulations are aimed at decreasing the amount of ground-level ozone in the air because, ground-level ozone is considered a pollutant. At the same time, many regulations are aimed at increasing the amount of ozone in the ozone layer. Despite the fact that ozone in the ozone layer is the same as ground-level ozone, ozone in the ozone layer is not considered a pollutant. Instead it is considered an essential substance, why?

Answer 24

Ground-level ozone is a pollutant because it is a poison, and it is where we can breathe it. Ozone in the ozone layer is not a pollutant because no one breathes that high up in the air, so its poisonous properties are unimportant. It is necessary in the ozone layer in order to block the sun’s ultraviolet rays.