C9 Reactions of acids [Paper 1] Flashcards
In terms of pH, what is an acid?
a solution with a pH of less than 7
In terms of pH, what is a neutral solution?
a solution with a pH of 7
In terms of H+ ions, what is an acid?
a substance that releases H+ ions when dissolved in water
How is the amount of H+ ions in a solution related to its pH?
The more H+ ions, the lower the pH
What are the names and formuale of theee main acids?
Hydrochloride acid, HCL; sulfuric acid, H2SO4; nitric acid, HNO3
How do you measure the pH of a substance?
Universal indicator or pH probe
What is a strong acid?
An acid where the molecules or ions completely ionise in water
What is a weak acid?
An acid where the molecules are ions partially ionise in water
What is a salt?
A compound formed when a metal ion takes the place of hydrogen ion in an acid
Which type of salts do sulphuric acid hydrochloric acid nitric acid form?
Sulphates, chlorides, nitrates
What are the products of a reaction between a metal and acid?
Salt + hydrogen
What are the products of a reaction between a metal hydroxide and an acid?
Salt + water
What are the products of a reaction between a metal oxide and an acid?
Salt + water
What are the products of a reaction between a metal carbonate and an acid?
Salt + water + carbon dioxide
What is a base?
Substance that reacts with acids in neutralisation reactions (eg an alkali)
What is an alkali?
Substance that dissolves in water to form a solution above pH seven
What is a neutralisation reaction?
A reaction between an acid and the base to produce water
What is the ionic equation for a reaction between an acid and an alkali?
H+ (aq) + OH- (aq) —> H2O (l)
How can you obtain a solid salt from a solution?
Crystallisation
When an acid reacts with a metal, which species is oxidised?
The metal
When an acid reacts with a metal, which species is reduced?
Hydrogen
