Chemistry. Exam

Does the mass/volume ratio stay the same if you cut a substance in half? Does the density change if you cut a substance in half?

The mass/volume ratio stays the same because they are being decreased by the same amount, the density does not change because the ratio stays the same.

IV

What the scientist changes

DV

What changes because of change in the IV

CV

What is kept the same all throughout

If mass is not changed, how can volume increase?

Volume can increase due to a temperature increase causing an increase in kinetic energy within molecules + expanding, thus decreasing density

Does density decrease as temperature increases? Why?

Yes, density does decrease, when molecules are heated up they cause an increase in kinetic energy, causing them to expand and increase volume (space between particles). Thus decreasing density.

When temperature is decreased, volume is also decreased.

Because of less kinetic energy between the particles

If volume is constant, and temperature is increased, what happens to the pressure?

The pressure increaseas because of more kinetic energy + the particles hit the wall more

If volume is increased while the temperature is constant, pressure decreaes.

This is because the substances don’t hit the sides as often, decreasing the pressure.

The pressure exerted by a gas in a container results from collisions between

Gas molecules and container walls

If you change the volume

Pressure will change if the number of particles stays the same

If volume is decreased, pressure increases because

Particle collisions

If you change temperature of a gas without changing pressure

Volume will change

Increase the temperature of the gas, volume will increase

Because particles have more kinetic energy and take up more space

If you change the temperature of a gas without changing volume

The pressure of a gas will change

If you increase the temperature of the gas, the pressure will

Also increase because they have more kinetic energy and will have more collisions