Subject:- Applied Chemistry 2.

Topic:- Fuels.

Difficulty:- Medium

1.5 gm of a coal sample was taken for C and H estimation by combustion method. The increase in weights of tube containing anhydrous CaCl2 and bulb containing KOH was found to be 1.25 gm and 4.88 gm respectively.

Calculate % of C and H.

C + O2 CO2 12 32 44 C% = weight of CO2 formed /weight of coal sample x12/44 x100 = 4.88/1.5 x12/44 x100 % of carbon in coal = 88.7 % 2H2 +O2 2H2O 4 32 36 2 16 18 H% = weight of H2O formed / weight of coal sample x2/18 x100 = 1.25/1.5x2/18 x100 = 9.25%