Reactions

Question 1

Chemical Reaction

Answer 1

Process of rearranging atoms in a substance. Signs of reaction includes change in colour, formation of a precipitate or there is energy emitted (heat, light). There are reactants (atoms that have bonds broken) and products (the results of the rearrangement)

Question 2

States of Reactants and Products

Answer 2

Solid (s), Gaseous (g), Liquid (l), Aqueous (aq)

Question 3

Temperature Changes

Answer 3

Increasing temperature gives reactants more energy meaning they come into contact more speeding up the reactions.

Question 4

Concentration

Answer 4

When there is a higher concentration of reactant molecules, they are more likely to collide initiating the reaction faster. Reducing the concentration would therefore slow the reaction down.

Question 5

Surface Area

Answer 5

Increasing the surface area of the reactant has the same effect as increasing concentration as there are more molecules that the reactants come into contact with

Question 6

Catalysts

Answer 6

There are a substance put into the reaction that increases its rate. They help the reactants form the product but do not affect the overall result. Reduces the required energy.

Question 7

Physical Change

Answer 7

A physical change is different to a chemical reaction as no new substances are formed. There may be a change in state but the change is reversible.