Water

Question 1

Latent heat of fusion

Answer 1

the amount of energy required to convert one mole of a substance from a solid to a liquid at its boiling point.

Question 2

Latent heat of vaporisation

Answer 2

the amount of energy required to convert one mole of a substance from a liquid to a gas at it’s boiling point.

Question 3

Density

Answer 3

a measure of the mass of a substance per unit volume (eg g/L)

Question 4

Specific heat capacity

Answer 4

the amount of energy required to raise the temperature of 1g of substance by 1 degree Celsius.

Question 5

Solution

Answer 5

an evenly distributed mixture of atoms, molecules or ions including a liquid solvent and one or more solutes.

Question 6

Solvent

Answer 6

the primary component of a solution, in which one or more solutes are dissolved.

Question 7

Solute

Answer 7

a substance which is dissolved in a solvent.

Question 8

Solubility

Answer 8

the degree to which a given solute will dissolve in a given solvent. Often expressed quantitatively with the units ‘g/100g solvent’

Question 9

Dissolution

Answer 9

the process of dissolving

Question 10

Miscible

Answer 10

a description of two liquids which mix together readily

Question 11

Immiscible

Answer 11

a description of two liquids which do not mix together readily

Question 12

Solvation

Answer 12

the process of water molecules surrounding a solvent molecule or ion and bonding with it

Question 13

Ionisation

Answer 13

a reaction between a molecule and water, resulting in the formation of two dissolved ions.

Question 14

Suspension

Answer 14

where a solid substance is dispersed in a solvent, but not dissolved. The solid particles are distinguishable from the solvent particles.

Question 15

Colloid

Answer 15

a stable suspension

Question 16

Dissociation

Answer 16

the process of an ionic compound dissolving

Question 17

Ion-dipole force

Answer 17

an attractive force between an ion and the oppositely charged pole of a polar molecule (such as water)

Question 18

Precipitate

Answer 18

a solid formed when two dissolved ionic compounds react to form an insoluble ionic compound

Question 19

Spectator Ion

Answer 19

an ion present in solution when a reaction occurs, but that does not participate in the reaction

Question 20

Ionic Equation

Answer 20

a chemical equation in which spectator ions are omitted.

Question 21

Molarity

Answer 21

the number of moles of solute per litre of solution

Question 22

ppm

Answer 22

parts per million: the concentration of a dissolved solute with the effective units of mg/L (in water) or μg/g.

Question 23

%w/w

Answer 23

the concentration of a dissolved solute with the effective units of g/100g.

Question 24

%w/v

Answer 24

the concentration of a dissolved solute with the effective units of g/100mL.

Question 25

%v/v

Answer 25

the concentration of a dissolved liquid solute, with the effective units of mL/100mL.

Question 26

Solubility Curve

Answer 26

a graphical depiction of how the solute concentration required to form a saturated solution changes across a range of temperatures.

Question 27

Saturated solution

Answer 27

a solution in which the maximum amount of solute is dissolved, at that temperature

Question 28

Unsaturated solution

Answer 28

a solution in which less than the maximum amount of solute is dissolved, at that temperature, and in which more solute could dissolve

Question 29

Supersaturated solution

Answer 29

a solution in which more than the maximum amount of solute is dissolved, at that temperature. This is an unstable situation which can arise when a saturated solution cools, and is likely to result in crystallisation of some of the solute.

Question 30

Crystallisation

Answer 30

where a dissolved solute forms a solid due to it being in a supersaturated solution. This often arises due to the cooling of a saturated solution; the slower the solution cools the larger the crystals appear.