Definitions

Question 1

Rate

Answer 1

The speed at which chemicals react.

Question 2

Covalent Bond

Answer 2

Electrostatic attraction between the shared electrons and the positive nuclei on either side

Question 3

How does a covalent bond work?

Answer 3

Electrostatic forces between negative electrons and positive nuclei.

Question 4

Ionic Bond

Answer 4

Electrostatic attraction between negative ions and positive ions.

Question 5

Ions

Answer 5

Charged particles.

Question 6

Isotope

Answer 6

Same atomic number but different mass number.

Question 7

Homologous Series

Answer 7

A family of compounds with the same general formula and a common chemical reaction.

Question 8

Saturated

Answer 8

Containing only single carbon to carbon bonds.

Question 9

Unsaturated

Answer 9

Containing carbon to carbon double bonds.

Question 10

Combustion

Answer 10

Reacting with oxygen to release heat energy.

Question 11

Isomer

Answer 11

Same molecular formula, different structure.

Question 12

Electrolysis

Answer 12

Breaking down of a substance using electricity.

Question 13

Covalent radius

Answer 13

Half the distance between the nuclei of two bonded atoms.

Question 14

Element

Answer 14

A substance made from only one type of atom

Question 15

Compounds

Answer 15

A substance made from more than one type of atom

Question 16

Ionisation energy

Answer 16

The amount of energy required to remove 1 mol electrons from 1 mol atoms in the gaseous state.

Question 17

LDFs

Answer 17

Attraction between temporary dipoles

Question 18

enthalpy change

Answer 18

Energy change during a reaction

Question 19

The minimum energy necessary for a successful collision

Answer 19

activation energy

Question 20

catalyst

Answer 20

A substance that lowers the activation energy and makes it easier for the intermediate activated complex to form

Question 21

enthalpy of combustion

Answer 21

The energy released when 1mol of a fuel burns completely in oxygen

Question 22

Displacement

Answer 22

A redox reaction where a metal high in the electrochemical series reacts with a metal compound lower in the electrochemical series.

Question 23

Haber Process

Answer 23

Production of ammonia from N and H at high pressure and temperature, with an iron catalyst.

Question 24

Le Chatelier’s principle

Answer 24

Equilibrium alters in the direction which counteracts the change of conditions.

Question 25

Mobile phase

Answer 25

In chromatography, the moving part of the process; eg, inert gas in GLC, or the solvent in paper

Question 26

Stationary phase

Answer 26

In chromatography, the phase other than the mobile phase. For example, the liquid in GLC.