Question

If the number of moles of an ideal gas in a firm container doubles while volume and temperature remain constant …

a. pressure doubles

b. pressure quadruple

c. pressure remains constant

d. pressure is reduced to half

e. pressure is reduced to a quarter

  

a

   

b

   

c

   

d

   

e

incorrect

IncorrectQuestion 2

0 / 1 pts

There are 3 balloons sitting next to each other, each of a different size. What is in the biggest one?

a. 3 moles H₂ (atomic mass of 2 AMU)

b. 2 moles Neon (atomic mass of 20 AMU)

c. 1 mole Xenon (atomic mass of 130 AMU)

d. it is impossible to determine

e. All three of these balloons would be almost the same volume

  

a

   

b

   

c

   

d

   

e

incorrect

IncorrectQuestion 3

0 / 1 pts

True or false: All of the energy of an ideal gas is in the form of potential energy.

  

True

   

False

incorrect

IncorrectQuestion 4

0 / 1 pts

What are some ways to increase the size of a balloon?

  

Increase its temperature

   

Decrease its temperature

   

Increase the number of moles of gas in it

   

Decrease the moles of gas in it.

   

Increase the pressure on the balloon.

   

Decrease the pressure on the balloon.

Incorrect. Think about the ideal gas law.

IncorrectQuestion 5

0 / 1 pts

Three lizards went to warm themselves in the sun. After an hour, the first lizard bragged, "I increased my temperature by 15 Kelvin." (Note- Kelvin is not a "degree" scale) The second lizard said, "That's nothing. I increased my temperature by 20 Celsius degrees." The third lizard said, "I have you all beat. I increased my temperature by 22 Fahrenheit degrees."

Which lizard actually experienced the biggest increase in temperature?

  

The first: 15K

   

The second: 20 C

   

The third: 22 F

   

It was a tie between the second and third.

Incorrect: The size of Celsius and Kelvin degrees are the same, but this is not true for Fahrenheit.

IncorrectQuestion 6

0 / 1 pts

If you decrease the temperature of an enclosed gas, and only one other attribute of the system changes, it would make sense for that other change to be what?

  

The pressure exerted by that gas decreases.

   

The volume of the container holding the gas increases.

   

The gas constant decreases.

   

The number of moles of the gas decreases.

Incorrect

IncorrectQuestion 7

0 / 1 pts

Select all of the following that are true

  

It is possible to determine the average kinetic energy of sample of gas molecules by directly measuring only the temperature of that sample.

   

As the temperature rises, the root mean squared velocity of the gas sample increases.

   

The molecules in a sample of massive gas will have a higher root mean squared velocity than the molecules in a sample of a less massive gas.

   

The hot air above a candle will be more dense than colder air surrounding it.

Incorrect

Question 8

1 / 1 pts

What temperature was the water on the bottom of any arctic lake in the middle of winter, 1986?

a. -5 degrees C

b. 0 degrees C

c. 4 degrees C

d. 10 degrees C

e. 31 degrees F

  

a

   

b

   

c

   

d

   

e

correct

Question 9

1 / 1 pts

When gas molecules collide with other molecules or the wall of the container...

  

The collision is inelastic, the molecules clump together, and fall to the ground.

   

The more massive molecules effuse out of the container faster

   

Pressure on the inside of the container is caused by the impulse conveyed when gas molecules collide with the walls of the container.

   

At the same temperature, both massive and less massive gas molecules will collide with the walls at the same average speed.

Correct

Question 10

1 / 1 pts

Jerry got a brass (0.0000187 m/mK) ring and encased it in pyrex glass (0.0000040 m/mK) to make it look cooler. He left it in the car on a hot summer day and found when he got back that the glass had cracked. He wondered who would want to break into his car and smash his ring. What do YOU think is the most likely to have happened?

a.  his girlfriend found it and thought it was a wedding ring

b. the glass absorbed too much sunlight

c. The brass expanded more than the glass around it when it got hot

d. a sudden drastic change in atmospheric pressure crushed the glass

  

a

   

b

   

c

   

d

correct

IncorrectQuestion 11

0 / 1 pts

You have a glass of water at 83 degrees C. You want to boil it by putting it in a vacuum. What is the smallest percentage of air molecules you would have to remove from the vacuum chamber to allow it to boil? Hint: to boil, the vapor pressure of water must be equal to the external pressure. (You will have to refer to a chart to figure out the vapor pressure of water at 83 degrees). (Remember, atmospheric pressure is 760 torr.) (Remember, pressure and number of moles of gas are directly proportional.)

  

25%

   

50%

   

75%

   

90%

Incorrect. Also think about the ideal gas law. You are changing pressure solely by removing moles of gas.

Answer 1

Question 1:-

If temperature and volume remain same, the pressure will depend upon the amount of the gas inside the container.

If n(number of moles) is doubled, pressure will become double.

a) is correct option.

Question 2:- If other things are same, volume of the balloon will be proportional to the amount of gas inside it. We know 1 mole of gas= 22.4 liter.

The more the moles, the more the volume.

H₂ have 3 moles. This will have largest volume.

(a) have correct answer.

Question 3:- Some energy of the gas is also in the form of kinetic energy. So this statement is false.

Question 4:-   this is the ideal gas equation.

Volume can be increased in 3 ways.

Increase the temperature.

Increase the number of moles of gas in it.

Decrese the pressure around it.