Unit 1 - Neutralisation

Question 1

What is a neutralisation reaction?

Answer 1

Neutralisation is the reaction of an acid with a base that results in the pH moving towards 7.

Neutralisation also moves the pH of an alkali down towards seven.

Question 2

What is the general equation when an acid is neutralised by an alkali (metal hydroxide)?

Answer 2

Acid + Alkali → Metal Salt + Water

Question 3

What is the general equation when an acid is neutralised by a metal oxide?

Answer 3

Acid + Metal oxide → Metal Salt + Water

Question 4

What is the general equation when an acid is neutralised by a metal carbonate?

Answer 4

Acid + Metal Carbonate → Metal Salt + Water + Carbon Dioxide

Question 5

How do you name the salt formed in a neutralisation reaction?

Answer 5

the metal ion from the alkali (or base) replaces the hydrogen ion from the acid - (alkali to front, acid to back). For example:

Hydrochloric Acid + Sodium Hydroxide → Sodium Chloride + Water

Hydrochloric acid…chloride

Sulfuric acid…sulfate

Nitric acid…nitrate

Question 6

What word is used to describe ions that are present during the reaction but are unchanged by the reaction, and so are present in the same state on both sides of the equation?

Answer 6

Spectator

Question 7

How would the following ionic equation be rewritten omitting the spectator ions?

H+(aq) + Cl-(aq) + Na+(aq) + OH-(aq) → Na+(aq) + Cl-(aq) + H2O(l)

Answer 7

H+(aq) + OH-(aq) → H2O(l)

Question 8

How would the following ionic equation be rewritten omitting the spectator ions?

2H+(aq) + 2NO3-(aq) + Ca2+(aq) + CO32-(aq) → Ca2+(aq) + 2NO3-(aq) + H2O(l) + CO2(g)

Answer 8

2H+(aq) + CO32-(aq) → H2O(l) + CO2(g)

Question 9

What is the purpose of a titration reaction?

Answer 9

This technique is commonly used in neutralisation reactions and to calculate an unknown concentration (of either the acid or alkali).