Chapter 7 Phases

Question 1

What type of energy is temperature?

Answer 1

Kinetic

Question 2

What is the key property of physical changes?

Answer 2

It is not intramolecular change, instead it is an intermolecular change. The molecules do not change such as when ice melts the h20 does not change, instead the bonding between other h20 molecules change.

Question 3

Name the three phase changes that take an increase in energy.

Answer 3

Fusion(melting) Vaporization(boiling) Sublimation
Fusion is solid to liquid
Vaporization is liquid to gas
Sublimation is solid to gas

Question 4

Name the three phase changes that release (decrease) energy.

Answer 4

Condensation Crystallization (Freezing) Deposition
Condensation is gas to liquid.
Crystallization is liquid to solid
Deposition is gas to solid

Question 5

Symbol for heat of transformation?

Answer 5

Delta H

Question 6

Equation that relates to a phase change

Answer 6

q=n x delta H
n= moles
n can also = m (mass)

Question 7

Equation for calorimetry phase change

Answer 7

q=(mc)DELTA(T)

c= the specific heat of the substance

Question 8

When is q=n x (DELTA)H used?

Answer 8

This is used when finding the transition heat.0

Question 9

Triple point

Answer 9

temp and pressure where all three phases exist at once

Question 10

critical point

Answer 10

marks the end of the liquid gas boundary, at this point the substance displays properties of both. The phase is no longer distinct.

Question 11

Supercritical Fluid

Answer 11

The point where the gas and liquid can not be discerned, also located at the critical point on a phase diagram.