How much coal calorific value 4500000cal is required to generate 1 ton of steam?

Answer 1

1 ton is about 1000 kg

Assuming water is already at 100 C (hot water that just has to boil)

it takes 40.7 KJ of energy to convert 1 mole of water to steam

1 cal = 4.184 J

1 mole water = 18 grams

4.5 x 106 cal per what mass of coal?? again I'll assume 1 ton of coal.

(1 ton Steam) x (1000 kg/ton) x (1000g/kg) = 1 x 106 grams

(1 ton water)x(106grams/ton)x(1mole/18grams)x(40.7x103 J/mole)x(1 cal/4.184J) = E

Where E represents the energy to vaporize 1 ton water measured in cal.

now divide this answer by the 4.5x106 cal/(ton??)

this will give the mass of coal needed assuming no heat loss to the environment.