236) Wood charcoal is produced by heating the wood at 100 Degree Centigrade.

237) The __________ is obtained when carbonisation of coal is carried out at 500 Degree Centigrade to 700 Degree Centigrade.

238) The bomb calorimeter is used for finding the __________ calorific value of solid and liquid fuels.

239) The efficiency of the Carnot cycle may be increased by

240) The atomic mass of sulphur is