Question

B

Answer 1

Answer:  1. magnesium hydroxide + sulfuric acid = magnesium sulphate + water

2. calcium hydroxide + hydrochloric acid = calcium  chloride + water

3. lead hydroxide + nitric acid =  lead nitrate + water

4. sodium hydroxide + sulfuric acid  =  sodium sulphate + water

5. potassium hydroxide + citric acid = potassium  citrate + water

6. silver hydroxide + hydrochloric acid = silver chloride + water

7.  aluminium hydroxide + phosphoric acid = aluminium phosphate + water

Explanation:

A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.  

The balanced chemical equations are :

1. magnesium hydroxide + sulfuric acid = magnesium sulphate + water

$Mg(OH)_2(aq)+H_2SO_4(aq)\rightarrow MgSO_4(aq)+2H_2O(l)$

2. calcium hydroxide + hydrochloric acid = calcium  chloride + water

$Ca(OH)_2(aq)+2HCl(aq)\rightarrow CaCl_2(aq)+2H_2O(l)$

3. lead hydroxide + nitric acid =  lead nitrate + water

$Pb(OH)_2(aq)+2HNO_3(aq)\rightarrow Pb(NO_3)_2(aq)+2H_2O(aq)$

4. sodium hydroxide + sulfuric acid  =  sodium sulphate + water

$NaOH(aq)+H_2SO_4(aq)\rightarrow Na_2SO_4(aq)+H_2O(l)$

5. potassium hydroxide + citric acid = potassium  citrate + water

$KOH(aq)+C_6H_8O_7(aq)\rightarrow C_6H_7O_7K(aq)+H_2O(l)$

6. silver hydroxide + hydrochloric acid = silver chloride + water

$AgOH(aq)+HCl(aq)\rightarrow AgCl(s)+H_2O(l)$

7.  aluminium hydroxide + phosphoric acid = aluminium phosphate + water

$Al(OH)_3(aq)+H_3PO_4(aq)\rightarrow AlPO_4(aq)+3H_2O(l)$