Acids, Bases and Salts quiz (Singapore O-Level Chemistry, SEAB 6092) quiz

Hydroxide ions

Hydrogen ions

Oxide ions

Carbonate ions

A strong acid is always more concentrated than a weak acid

A strong acid contains more water than a weak acid

A strong acid ionises completely while a weak acid ionises only partially

A weak acid does not release any hydrogen ions

$\text{H}^+(aq) + \text{OH}^-(aq) \rightarrow \text{H}_2\text{O}(l)$

$\text{H}^+(aq) + \text{O}^{2-}(aq) \rightarrow \text{OH}^-(aq)$

$\text{Na}^+(aq) + \text{Cl}^-(aq) \rightarrow \text{NaCl}(s)$

$\text{H}_2(g) + \text{O}_2(g) \rightarrow \text{H}_2\text{O}(l)$

Sodium oxide

Carbon dioxide

Water

Aluminium oxide

pH 1, strongly acidic

pH 13, strongly alkaline

pH 7, neutral

pH 4, weakly acidic

Litmus is poisonous

Universal indicator gives a colour for the whole pH range, not just acid or alkali

Litmus only works in alkalis

Universal indicator changes colour faster

Titration

Adding excess metal to an acid

Precipitation by mixing two soluble solutions

Heating a carbonate

To make the salt more concentrated

To speed up evaporation

To change the colour of the solution

To ensure all the acid reacts, so none is left to contaminate the salt

Effervescence as carbon dioxide is released

A blue colour appears

No visible change

A white precipitate forms immediately

A salt and water

A salt and hydrogen

A salt, water and carbon dioxide

An oxide and hydrogen

It decreases

It stays the same

It increases

It becomes zero

Sodium chloride is insoluble

Sodium chloride decomposes on heating

Hydrochloric acid is a weak acid

Sodium hydroxide is a soluble base, so excess could not be filtered off

Evaporate to the point of crystallisation, cool, then filter and dry the crystals

Boil the solution to dryness over a strong flame

Add more acid

Filter immediately without heating

Red

Blue

Green

Colourless