Unit 1B: Solids, Liquids, & Gases

Question 1

Kinetic theory

Answer 1

All matter consists of tiny particles that are in constant motion

Question 2

Gas pressure

Answer 2

The result of simultaneous collisions of billions of rapidly moving particles in a gas with an object

Question 3

Atmospheric pressure

Answer 3

Results from the collisions of atoms and molecules in air with objects

Question 4

Pascal (Pa)

Answer 4

The SI unit of pressure, 1 atm = 100,000 Pa = 1 kPa

Question 5

Standard atmosphere (atm)

Answer 5

The pressure required to support 760 mm Hg in a mercury barometer at 25*C

Question 6

Combined gas law

Answer 6

If the amount of gas is constant, P1V1/T1 = P2V2/T2

Question 7

Ideal gas law constant

Answer 7

R = 8.31 (LkPa)/(Kmol)

Question 8

Ideal gas law

Answer 8

PV = nRT

Question 9

Partial pressure

Answer 9

The contribution each gas in a mixture makes to the total pressure exerted by the gas

Question 10

Dalton’s law of partial pressure

Answer 10

At constant volume and temperature, the total pressure exerted by a mixture of gases is equal to the sum of the partial pressure of the component gases:
P(total) = P1+P2+P3+…

Question 11

Surface tension

Answer 11

The inward force that tends to minimize the surface area of a liquid

Question 12

Surfactant

Answer 12

Any substance that interferes with the hydrogen bonding between water molecules and reduces surface tension

Question 13

Aqueous solution

Answer 13

Water that contains dissolved substances

Question 14

Solvent

Answer 14

The dissolving medium in a solution

Question 15

Solute

Answer 15

The dissolved particles in a solution

Question 16

Electrolyte

Answer 16

A compound that conducts an electric current when it is in an aqueous solution or its molten state

Question 17

Hydrate

Answer 17

A compound that contains water of hydration (the water contained in a crystal)

Question 18

Describe the assumptions of kinetic theory as it applies to gases.

Answer 18

• the particles in a gas are considered to be small, hard spheres with an insignificant volume,
• There are no attractive forces between molecules.

Question 19

Convert atm’s to kPa’s.

Answer 19

1 atm = 101.3 kPa

Question 20

Understand the Kelvin scale and how it relates to kinetic energy.

Answer 20

The Kelvin scale is directly proportionate to the average kinetic energy of the molecules.
K = *C+273

Question 21

Explain the role of external pressure in determining the boiling point of a liquid (pages 392-395).

Answer 21

With less external pressure, the molecules within the liquid can break away easier. When pressure decreases, the boiling point also decreases.

Question 22

How do crystal systems differ?

Answer 22

In the patterns in which their molecules are arranged, which effects the shape of the crystal

Question 23

How does pressure affect the movement of gas particles?

Answer 23

The higher the pressure, the higher the temperature if all other factors remain constant

Question 24

Boyle’s law

Answer 24

P1V1 = P2V2

Question 25

How are real gases different from ideal gases?

Answer 25

- Ideal gases follow all the gas laws under all conditions | - The particles in an ideal gas would have no volume and there would be no attraction between the particles

Question 26

Be able to predict which molecules would be soluble in water.

Answer 26

Ionic compounds and polar covalent molecules

Question 27

Suspension

Answer 27

A mixture from which the particles settle out upon standing; largest particles

Question 28

What causes Brownian motion?

Answer 28

The chaotic movement of colloidal particles

Question 29

List three factors that can affect gas pressure.

Answer 29

- volume (V), measured in liters - temperature (T), measured in kelvins - number of moles (n)

Question 30

Explain why ice is less dense than liquid water.

Answer 30

The positively charged hydrogen atoms in the water molecules keep the negatively charged oxygen atoms of other water molecules at a set difference away. The water molecules in ice are arranged in a regular framework like a honey comb. This means the water molecules in ice are farther apart than in liquid water.

Question 31

Charles’s law

Answer 31

V1/T1 = V2/T2 *Temp is in Kelvins

Question 31

Gay-Lussac’s law

Answer 31

P1/T1 = P2/T2 *Temp is in Kelvins

Question 32

Colloids

Answer 32

A mixture containing particles of medium size (1 nm- 1000 nm)

Question 33

Solutions

Answer 33

A homogeneous mixture that has tiny particles that can't be filtered out