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PhET States of Matter

Last updated over 6 years ago

8 questions

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To accompany PhET States of Matter

Question 1

1.

Click on the different types of molecules. What do you notice about the difference between oxygen molecules and neon molecules?

Question 2

2.

Click on Argon and change it to a liquid. Observe for about 10 seconds. What do you notice?

Some individual molecules do not move.

Most molecules will stay at the top of the container.

A few molecules will begin colliding all the way to the top of the container.

The molecules tend to be very spread apart.

Question 3

3.

Click on the oxygen particle and make it a gas. Add heat above 350 K (kelvin is another way to measure temperature). Which of these statements is true?

Molecules are less likely to hit the walls of the container at this level of heat compared to 100K.

The molecules are breaking free from 2 particles to only 1.

Molecules are slowing down and their attractions bring them together.

Question 4

4.

Select water and make it as solid. Lower the temperature to 50K. What do you notice?

The molecules stop moving.

The molecules grow more dense (closely packed).

The molecules grow less dense (spread apart).

Attractions between molecules weaken and they spread apart.

Question 5

5.

Go to the bottom of the simulator and select "phase changes." Select oxgyen and then add pressure by pulling up on the pump and pushing it down until the pressure gauge says 20 atm. Then drag the finger down to push the lid down. As you increased the pressure, what happens to the temperature?

It goes up.

There is no change.

It goes down.

Question 6

6.

Besides using the pump or finger to press down on the lid, how else can you increase the pressure in the container?

Question 7

7.

Click on neon and push the finger down so that the lid is halfway down the container (the thumb just touches the top). If you cool the molecules down by adding ice, what temperature will you need to reach in order to make the pressure go down just below 50 atm? (Choose the closest number.)

At around 100K

At around 65K  

At around 40K

At around 20K

Question 8

8.

Which molecule is LEAST condensed at below 30K?

neon

argon

oxygen

water

Molecuels are bouncing off each other more and are hitting container walls more than at 100K.