Revision balance the equation

Chemical equation

1. Balance the following equations

(a) CaCO3  CaO + CO2

(b) NaNO3  NaNO2 + O2

(c) Na + O2  Na2O

(d) NaHCO3  Na2CO2 + CO2 + H2O

(e) CH4 + O2  CO + H2O

(f) Fe2O3 + CO  Fe + CO2

(g) Fe2O3 + C  Fe + CO

(h) Al + HCl  AlCl3 + H2

(i) MnO2 + HCl  MnCl2 + Cl2 + H2O

2. 11. 3g of potassium chlorate(I) KClO is heated strongly to produce potassium chloride and oxygen in laboratory.Find the volume of gas produced at s.t.p
( 1 mole gas = 22.4dm3, K= 39, Cl=35.5 )

3. An aqueous solution of sodium thiosulphate Na2S2O3, reacts with dilute hydrochloric acid to produce sodium chloride,sulphur dioxide,sulphur and water.
If 15.8g sodium thiosulphate is used, calculate
(a) the mass of sodium chloride produce
(b) the mass of sulphur produced
(c) the volume of sulphur dioxide produced
(d) the number of molecules of sulphur dioxide produced
( S=32, O=16, Na=23, 1 mole gas at s.t.p= 22.4dm3)

4. Ammonia is obtained through the following reaction.
N2 + 3H2  2NH3
Calculate the number of moles and volumes of nitrogen and hydrogen used in the
reaction if 3.2 moles of ammonia are produce at s.t.p

5. Write down the chemical equations of thefollowing reactions
(a) Buthane,C4H10 is heated in air to produce carbon and water
(b) Ammonia reacs with copper(II) oxide to produce copper,nitrogen and water
(c) Aluminium reacts with iron(III) oxide to give iron and aluminium oxide
(d) Magnesium carbonate produces magnesium chloride,carbon dioxide and water when dilute nitric acid is added to it.