1. Making Salts Soluble salt Insoluble salt Acid + excess insoluble solid
Acid + alkali
titration
Acid + reactive metal
Soluble salt
Acid + base
Acid + carbonate
Insoluble salt
Direct combination
Precipitation

2. Reactions of acids
Neutralisation of:
hydrochloric acid gives a chloride
sulphuric acid gives a sulphate
nitric acid gives a nitrate
Acid + metal  salt + hydrogen
Acid + base*  salt + water
Acid + carbonate  salt + water + carbon dioxide
*Base: A metal oxide or metal hydroxide.
An alkali is a water-soluble base.

3. Salts
A salt is an ionic compound which is neither an acid (containing H+) or a base (containing O2- or OH-). A salt is formed whenever an acid is neutralised.
Acids, containing H+
Salts
Ionic compounds
Bases, containing OH- or O2-

4. Uses of Salts Plant fertilisers (NPK) Food flavour and preservation
(NH4)2SO4, NH4NO3, KH2PO4, …….
Food flavour and preservation
NaCl, KCl, KNO3…….
In toothpaste
NaF
Photographic film
AgCl, AgBr

5. Salts are important also in:
Proteins and enzymes
The molecules that carry out the chemical reactions of life
DNA and RNA
the molecules of inheritance
Transmission of electrical impulses along nerves

6. Acid Neutralisation reactions
Neutralisation of:
hydrochloric acid gives a chloride (containing Cl-)
sulphuric acid gives a sulphate (containing SO42-)
nitric acid gives a nitrate (containing NO3-)
Acid + metal  salt + hydrogen
Acid + base  salt + water
Acid + carbonate  salt + water + carbon dioxide

7. Methods of salt making (1)
Acid + alkali  salt + water
HCl (aq) + NaOH (aq)  NaCl (aq) + H2O (l)
Titration of acid against alkali for soluble salts of group 1 metals and ammonium
5 cm3 sodium hydroxide solution was measured using a pipette and transferred to the conical flask. 2 drops of methyl orange indicator were added. Hydrochloric acid was poured into the burette and the starting reading was recorded. The acid was added to the sodium hydroxide, drop by drop, until the indicator turned from yellow to orange (or red). Charcoal was added to the mixture to absorb the indicator and was removed by filtration. Water was evaporated from the filtrate, leaving sodium chloride crystals.

8. Methods of salt making (2)
Acid + excess insoluble solid
For all other soluble salts
Solid is either a moderately reactive metal, a base or a carbonate
Excess solid to react with all the acid
Removed by filtration

9. Methods of salt making (3)
Precipitation reactions
To make insoluble salts
2 solutions each containing one of the ions in the salt are mixed.
Salt is precipitated
Salt is filtered, residue is washed on filter paper and dried.

10. Methods of salt making (4)
Direct combination of the elements
sodium (l) + chlorine (g)  sodium chloride (s)
2 Na (l) Cl2 (g)  2 NaCl (s)
aluminium (s) + bromine (l)  aluminium bromide (s)
2 Al (s) Br2 (l)  2 Al Br3 (s)

11. Methods of salt making (1)
barium hydroxide (aq) + nitric acid (aq)
Ba(OH)2 (aq) HNO3 (aq) 2
barium nitrate (aq) + water (l)
Ba(NO3)2 (aq) H2O (l) 2

12. Methods of salt making (1)
(b)
ammonium carbonate (aq) + sulphuric acid (aq)
(NH4)2CO3 (aq) H2SO4 (aq)
ammonium sulphate (aq) + water (l) + carbon dioxide (g)
(NH4)2SO4 (aq) H2O (l) + CO2 (g)

13. Methods of salt making (1)
(c)
ammonium hydroxide (aq) + nitric acid (aq)
NH4OH (aq) HNO3 (aq)
ammonium nitrate (aq) + water (l)
NH4NO3 (aq) H2O (l)

14. Methods of salt making (1)
potassium hydroxide (aq) + nitric acid (aq)
KOH (aq) HNO3 (aq)
potassium nitrate (aq) water (l)
KNO3 (aq) H2O (l)

15. Methods of salt making (2)
Acid + insoluble base  salt + water
H2SO4 (aq) + CuO (s)  CuSO4 (aq) + H2O (l)

16. Methods of salt making (2)
calcium (s) nitric acid (aq)
Ca (s) HNO3 (aq) 2
calcium chloride(aq) hydrogen (g)
Ca(NO3)2 (aq) H2 (g)

17. Methods of salt making (2)
iron (s) sulphuric acid (aq)
Fe (s) H2SO4 (aq)
iron (II) sulphate (aq) hydrogen (g)
FeSO4 (aq) H2 (g)

18. Methods of salt making (2)
calcium carbonate (s) + nitric acid (aq)
CaCO3 (s) HNO3 (aq) 2
calcium nitrate (aq) + water (l) + carbon dioxide (g)
Ca(NO3)2 (aq) H2O (l) + CO2 (g)

19. Acid + metal  salt + hydrogen
Magnesium + hydrochloric acid  magnesium chloride + hydrogen
Mg (s) HCl (aq)  MgCl2 (aq) H2 (g)
Mg (s)
+ 2 H+ 2 Cl- (aq) 
Mg2+ 2 Cl- (aq)
+ H2 (g)
2 e-
copper + hydrochloric acid  no reaction
Cu (s) HCl (aq)
Cu (s)
+ 2 H+ 2 Cl- (aq)

20. Metal Reactivity Series
Potassium
Sodium
Lithium
Calcium
Magnesium
Zinc
Iron
Lead
Hydrogen
Copper
Silver
Gold
Platinum
React with cold water
React with dilute acids and steam
Reactivity
Do not react with dilute acids and steam

21. Acid + base  salt + water
Sulphuric acid copper oxide  copper sulphate + water
H2SO4 (aq) CuO (s)  CuSO4 (aq) H2O (l)
2 H+ SO42- (aq)
+ Cu2+ O2- (s) 
Cu2+ SO42- (aq)
+ H2O (l)
Sulphuric acid + copper hydroxide  copper sulphate + water
H2SO4 (aq) Cu(OH)2 (s)  CuSO4 (aq) H2O (l)
2 H+ SO42- (aq)
+ Cu2+ 2 OH- (s) 
Cu2+ SO42- (aq)
+ 2 H2O (l)

22. Carbonic acid H2CO3 (aq) 2 H+ CO32- (aq) Present in fizzy drinks:
H2CO3 (aq)  CO2 (g) + H2O (l)

23. Acid +carbonate  salt + water + carbon dioxide
Sulphuric acid + nickel carbonate  nickel sulphate + water + carbon dioxide
H2SO4 (aq) + NiCO3 (s)  NiSO4 (aq) + H2O (l) + CO2 (g)
2 H+ SO42- (aq)
+ Ni2+ CO32- (s) 
Ni2+ SO42- (aq)
+ H2O (l) + CO2 (g)
+ H2CO3 (aq)