Chapter 13 - States Of Matter

Question 0

Kinetic theory

Answer 0

All matter consists of tiny particle that are in constant motion.

Question 1

Kinetic energy

Answer 1

The energy an object has because of its motion.

Question 2

What are the assumptions of the kinetic theory as it applies to gasses?

Answer 2

• the particles of a gas are small, hard spheres with insignificant volume.
• the motion of the particles in gas are rapid, constant and random.
• all collisions between particles in a gas are perfectly elastic.

Question 3

Gas pressure

Answer 3

Results from the force exerted by a gas per unit surface area of an object.

Question 4

How does kinetic theory explain gas pressure?

Answer 4

Gas pressure is the result of billions of rapidly moving particles in a gas simultaneously colliding with an object.

Question 5

Vacuum

Answer 5

An empty space with no particles and no pressure.

Question 6

Atmospheric pressure

Answer 6

The collisions of atoms and molecules in air with objects.

Question 7

Barometer

Answer 7

A device that is used to measure atmospheric pressure.

Question 8

What is the SI unit of pressure?

Answer 8

Pascal (Pa).

Question 9

Standard atmosphere (ATM)

Answer 9

1 ATM = 760 mm hg = 101.3 kPa

Question 10

What is the relationship between the temperature in kelvins and the average kinetic energy of particles?

Answer 10

The kelvin temperature of a substance is directly proportional to the average kinetic energy of the particles of the substance.

Question 11

What factors determine the physical properties of a liquid?

Answer 11

The interplay between the disruptive motions of particles in a liquid and the attractions among the particles determines the physical properties of liquids.

Question 12

What is the relationship between evaporation and kinetic energy?

Answer 12

During evaporation, only those molecules with a certain minimum kinetic energy can escape from the surface of the liquid.

Question 13

Vapor pressure

Answer 13

A measure of the force exerted by a gas above a liquid.

Question 14

Under what conditions does boiling occur?

Answer 14

When a liquid is heated to a temperature at which particles throughout the liquid have enough kinetic energy to vaporize, the liquid begins to boil.

Question 15

Boiling point

Answer 15

The temperature at which the vapor pressure of the liquid is just equal to external pressure on the liquid.

Question 16

Normal boiling point

Answer 16

The boiling point of a liquid at a normal pressure.

Question 17

How are the structure and properties of solids related?

Answer 17

The general properties of solids reflect the orderly arrangement of their particles and the fixed locations of their particles.

Question 18

Melting point

Answer 18

The temperature at which a solid changes into a liquid.

Question 19

Freezing point

Answer 19

The temperature at which a liquid changes into a solid.

Question 20

Crystal

Answer 20

The particles are arranged in an orderly, repeating, three dimensional pattern called a crystal lattice.

Question 21

What determines the shape of a crystal?

Answer 21

The shape of a crystal reflects the arrangements of the particles within the solid.

Question 22

Unit cell

Answer 22

The smallest group of particles within a crystal that retains the geometric shape of the crystal.

Question 23

Allotropes

Answer 23

Two or more molecular forms of the same element in the same physical state.

Question 24

Amorphous solid

Answer 24

Lacks an ordered internal structure. Their Stimson are randomly arranged.

Question 25

Sublimation

Answer 25

The change of a substance from a solid to a vapor without passing through the liquid state.

Question 26

When can sublimation occur?

Answer 26

Sublimation occurs in solids with vapor pressures that exceed atmospheric pressure at room temperature.