Education and Career Forum

calculate the ratio between the energy Q1 required to boil off 10kg of water at 100 degree celeius and the energy Q2 requierd to raise the temperature of 10 kg of water from 0 degree celeies to 100 degree?

10kg water = 10,000g water

The latent heat for boiling water is 540 cal/g. That means that 1g of water requires 540 cal of heat to boil.

Thus, 10,000g requires 10,000 x 540 = 5400000 cal to boil.

So,

Q1= 5400000 calorie.


The specific heat of water is 1.00 cal/g-C, that means that 1.00 calorie is needed to raise 1g of water 1C. Thus, it would take 10000 x 1.00 calories to raise 10000g up 1C and 100 x 10000 x 1.00 = 1000000 cal to raise the water to its boiling point.

So,

Q2= 1000000 calorie.


So ratio of Q1:Q2 = 5400000:1000000 = 27:5