Unit 2: Pressure

Question 1

Wooshies

Answer 1

As the particles go faster, add more lines. Wooshies behind the particle makes it go faster

Question 2

Air pressures basics

Answer 2

• Based off of collisions

- Is force divided by area

Question 3

Temp conversion Celsius to kelvin

Answer 3

Plus 273

Question 4

Temp conversion Kelvin to Celsius

Answer 4

Minus 273

Question 5

What pressure measurements are exact

Answer 5

• Atm
• mmhg
• torr (torr which means the same as inches of mercury)

Question 6

Not defined pressure measurements

Answer 6

• PSI
• inHg
• KPA
• STP

Question 7

Kinetic molecular theory general

Answer 7

-Matter is composed of particles that are in constant motion

Question 8

Where does pressure of gas come from

Answer 8

-Pressure of a gas is due to collisions with the side of the container.

Question 9

Water and mercury column problem

Answer 9

• Mercury density of 13.6 g/ml and it rises 760 mm at standard pressure
• Water has density of 1.00 g/ml how far does it rise
• Pressure is the same bc they have the same dish and column and the atmospheric pressure puts force on each equally
• Divide 13.6 by 1.00 (both g/ml so they cancel out) and you find that water is 13.6 times lighter than mercury, so if they are acted upon by the same pressure, the water should rise 13.6 times higher than mercury ( 760 times 13.6)

Question 10

KMT theory Diffusion

Answer 10

Particles of substances mix slowly (diffuse) due to collisions of particles that produce random motion

Question 11

KMT theory temperature

Answer 11

Changing the temperature changes the speed of the particles

-Temperature is a measure of kinetic energy of a substance

Question 12

KMT theory gas collsiions

Answer 12

In a gas, particles are far enough apart that we can ignore attractive and repulsive forces. We assume collisions are elastic
-Pressure of a gas is due to collisions with the sides of the container P= force divided by area

Question 13

KMT theory gas component relationships

Answer 13

-All gases ideally act the same, so the relationships between the variables of pressure, temperature, and volume, and amount are predictable

Question 14

How does a barometer work

Answer 14

Barometer is used-> atmospheric pressure increases, mercury pushed up column

Question 15

What happens to air pressure if temperature Increases and decreases and why

Answer 15

Barometer is used-> atmospheric pressure increases, mercury pushed up column
If temperature decreases, air pressure decreases because force decreases (like soccer ball in winter)

Question 16

Why don’t we feel pressure

Answer 16

We don’t feel pressure because pressure in and pressure out so it cancels out. Some people are sensitive with pressure and can tell when rain is coming

Question 17

Atmospheric pressure

Answer 17

• Pushes/collides with objects
• Small particles collide with container or solids and with other gases
• Force applies by the air and other particles in the atmopsheee
• Particles collide with container (me, chair, straw) and exert force
• Mention pressure is force over area

Question 18

You need to loosen a stuck jar lid so you run it under hot water why does it work

Answer 18

Hot water= molecules speed up= collide more and harder= expand volume