definitions to learn

Question 1

relative atomic mass

Answer 1

the average mass of all isotopes in an element, compared to the mass of one atom of carbon-12

Question 2

solution

Answer 2

a mixture of a solvent and a solute that does not separate out

Question 3

intermolecular forces

Answer 3

the forces that exist between molecules

Question 4

activation energy

Answer 4

the minimum amount of energy needed for a chemical reaction to occur

Question 5

exothermic reaction

Answer 5

reactions transfer energy into the surroundings (temperature increase) but the reactions themselves lose energy (temperature decrease)

Question 6

endothermic reaction

Answer 6

reactions take energy from the surroundings (temperature decrease) but the reactions themselves gain energy (temperature increase)

Question 7

Cracking

Answer 7

A process that involves breaking down larger hydrocarbons to produce smaller
more useful molecules.

Question 8

Enthalpy change

Answer 8

The overall change in energy (shown as delta H)