Chapter 3 Vocabulary

Question 1

Polar Molecule

Answer 1

A polar molecule is one where opposite ends have opposite charges.

Question 2

Cohesion

Answer 2

Cohesion is the way that water molecules stick to one another. Cohesion due to hydrogen bonding contributes to the transport of water and dissolved nutrients against gravity in plants.

Question 3

Adhesion

Answer 3

Adhesion is the clinging of one substance to a another, such as the adhesion of water to the wall of the cells. This helps counter the downward pull of gravity.

Question 4

Surface Tension

Answer 4

Surface tension is how difficult it is to stretch or break the surface of a liquid.

Question 5

Kinetic Energy

Answer 5

Kinetic energy is the energy of motion. Anything that moves has kinetic energy.

Question 6

Heat

Answer 6

Heat is the measure of the total amount of kinetic energy due to molecular motion in a body of matter.

Question 7

Temperature

Answer 7

Temperature measures the intensity of heat due to the AVERAGE kinetic energy of the molecules.

Question 8

Celsius scale

Answer 8

Used to indicate temperature.

• 0 Degrees Celsius= freezing water
• 100 Degrees Celsius= boiling water

Question 9

calorie(cal)

Answer 9

The unit calorie is the amount of heat it takes to raise the temperature of 1 gram of water by 1 degree Celsius.

Question 10

kilocalorie(kcal)

Answer 10

The unit kilocalorie is the amount of heat it takes to raise the temperature of 1 kilogram of water by 1 degree Celsius.

Question 11

Specific Heat

Answer 11

The specific heat of a substance is the amount of heat that must be absorbed or lost in order to change the substance’s temperature by 1 degree Celsius.

Question 12

Evaporative Cooling

Answer 12

Evaporative cooling is when the “hottest” molecules leave as gas(highest kinetic energy), causing the other molecule to cool down.

Question 13

Solution

Answer 13

A liquid that is a completely homogeneous mixture of two or more substances is a solution.

Question 14

Hydrophilic

Answer 14

Anything that is hydrophilic has an affinity for water(ionic or polar).

Question 15

Hydrophobic

Answer 15

Substances that repel water are hydrophobic(non polar or non-ionic)

Question 16

Solute

Answer 16

The substance that is dissolved is the solute.

Question 17

Solvent

Answer 17

The dissolving agent is the solvent.

Question 18

Aqueous Solution

Answer 18

In an aqueous solution, the water is the solvent.

Question 19

mole

Answer 19

Represents an exact number of objects

*6.02 X 10^23

Question 20

Molecular Weight

Answer 20

Molecular weight is the ratio of the average mass of one molecule of an element(or compound) to 1/12 the mass of the C12 atom.

Question 21

Hydrogen Ion

Answer 21

A single proton with a charge of +1.(H+1)

Question 22

Molarity

Answer 22

The number of moles of solute per liter of solution.

Question 23

Hydroxide Ion

Answer 23

A water molecule that lost a proton.(OH-)

Question 24

Acid

Answer 24

A substance that increases the hydrogen ion concentration in a solution.

Question 25

Base

Answer 25

A substance that reduces the hydrogen ion concentration in a solution.

Question 26

Buffer

Answer 26

Buffers are substances that minimize changes in the concentration of H+ and OH- in a solution.

Question 27

pH Scale

Answer 27

The pH of a solution is the negative logarithm(base 10) of the hydrogen ion concentration.

Question 28

Acid Precipitation

Answer 28

Acid Precipitation refers to rain, snow, or fog with a pH lower than 5.6. Usually, uncontaminated rain is slightly acidic due to the formation of carbon dioxide with water.
*Caused by sulfur oxides and nitrogen oxides