Physical Science Test 2

Question 1

Define Absolute humidity

Answer 1

The mass of water vapor contained in a certain volume of air

Question 2

Define relative humidity

Answer 2

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

Question 3

Define green house effect

Answer 3

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

Question 4

Define parts per million

Answer 4

The number of molecules or atoms of a substance in a mixture for every one million molecules or atoms in the mixture

Question 5

The temperature is the same at 1 pm on two consecutive days. For the person outside working, the second day feels cooler than it does on the first day. On which day was the relative humidity higher?

Answer 5

The humidity was higher on the first day. Since the person felt cooler on the second day, his sweat must of evaporated quicker on the first day. Thus the first day was more humid.

Question 6

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

Answer 6

If the relative humidity is 100%, the air can not hold any more water. There won’t be any evaporation

Question 7

A child decides to keeps a goldfish in a small bowl. He has to add water every day to keep the bowl full. Two day in a row and the temperature is very similar but on the first day the humidity is 90% and on the second day in the humidity is 60%. Which day will the the child add more water to the bowl?

Answer 7

The child will add more water to the bowl on the second day. When the humidity is lower, water evaporates faster.

Question 8

Why does sweat cool people down?

Answer 8

Sweat cools you down because when it evaporates, it takes energy from your skin. When energy leaves your skin, it gets cooler.

Question 9

What is the percentage of nitrogen in dry air? What about oxygen?

Answer 9

Dry air is 78% nitrogen and 21% oxygen

Question 10

What would be the consequences of removing the carbon dioxide from the earths air supply?

Answer 10

If the air had no carbon dioxide, the earth would be colder. Since carbon dioxide is a greenhouse gas, the greenhouse effect would be weaker, leaving a cool earth. Also, plants would die of starvation.

Question 11

What would be the consequences of removing all the ozone from the earth’s air supply?

Answer 11

Without ozone, ultraviolet light would kill a lot of living beings.

Question 12

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

Answer 12

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

Question 13

Define humidity:

Answer 13

The moisture content of air

Question 14

Suppose astronomers found another solar system in which there was a sun just like our sun. Suppose further that a planet in this new solar system was just as far from the sun as we are to our sun. Since the vast majority of the energy planets get from there Suns, is it reasonable to assume that the new planet would have roughly the same average temperature as that of earth. Why or why not?

Answer 14

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

Question 15

What makes the majority of the air we exhale?

Answer 15

Nitrogen

Question 16

Do we exhale more carbon dioxide or oxygen?

Answer 16

exhale more oxygen

Question 17

Do the data indicate any significant global warming?

Answer 17

No. Figure 2.6 shows the average temperature has been reasonably consistent for the past 80 years.

Question 18

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

Answer 18

See study guide

Question 19

Suppose you had a sample of air in which the concentration of nitrogen oxides is 0.023 percent but with the concentration of nitrogen oxides be if you expressed it is ppm?

Answer 19

See study guide

Question 20

Is the air cleaner today or was it clean or 30 years ago?

Answer 20

Air is much cleaner today than it was 30 years ago

Question 21

What is cost/benefit analysis?

Answer 21

A cost/benefit analysis attempts to determine whether or not to take an action by determining The benefits of the action as well as the cost. Is the benefit outweighs the cost, the action should be taken. It’s not the action should be not taken

Question 22

What does a catalytic converter do in a car?

Answer 22

The catalytic converter converts carbon monoxide it in the cars exhaust to carbon dioxide. The fact that most cars have these today is one of the main things are responsible for reducing the carbon monoxide concentration in the air by more than 70% since 1975.

Question 23

What does a scrubber doing a smokestack?

Answer 23

A scrubber traps sulfur oxide in a smokestack and keeps them from being emitted into the air. They are one of the reasons there has been more than 70% decrease in sulfur oxides concentration in the air

Question 24

In the United States, 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 needs that high up in the air, so it’s poisonous properties are unimportant. It is necessary in the ozone layer in order to block the sun ultraviolent to rays.