module 2: 4.1 acids, bases and neutralisation

Question 1

what happens to acids when dissolved in water

Answer 1

they release hydrogen ions as protons (H+) into the solution

HCl(g) + aq —> H+ (aq) + Cl- (aq)

Question 2

define strong acid

Answer 2

a strong acid (such as HCl) releases all its hydrogen atoms into the solution as H+ ions and completely dissociates in aq solution

Question 3

define weak acid

Answer 3

a weak acid (such as CH3COOH) only releases a small proportion of its available hydrogen atoms into the solution as H+ ions. It partially dissociates in aq solution

Question 4

examples of bases and what they form

Answer 4

metal oxides, metal hydroxides, metal carbonates and ammonia are bases.
It nutrealises to form an acid and salt.

Question 5

define alkali

Answer 5

an alkali is a base that dissolves in water releasing hydroxide ions (OH-) into the solution.
NaOH(s) + aq —> Na+ (aq) + OH- (aq)

Question 6

neutralisation reaction (no carbonates)

Answer 6

acid + metal oxide/hydroxide/alkali –> salt + water

Question 7

neutralisation reaction with carbonates

Answer 7

acid + metal carbonate —> salt + water + carbon dioxide