A tube leads from a flask in which water is boiling under atmospheric pressure to a calorimeter. The mass of the calorimeter is 150 gm, its specific heat capacity is 0.1 cal/gm/∘C, and it contains originally 340 gm of water at 15∘C. Steam is allowed to condense in the calorimeter until its temperature increase to 71∘C, after which total mass of calorimeter and contents are found to be 525 gm. Compute the heat of condensation of steam.
A tube leads from a flask in which water is boiling under atmospheric pressure to a calorimeter. The mass of the calorimeter is 150 gm, its specific heat capacity is 0.1 cal/gm/∘C, and it contains originally 340 gm of water at 15∘C. Steam is allowed to condense in the calorimeter until its temperature increase to 71∘C, after which total mass of calorimeter and contents are found to be 525 gm. Compute the heat of condensation of steam.
The correct option is D 539 cal/gm
Mass of calorimeter and contents before passing
Steam = (150 + 340) = 490 gm.
Mass after passing steam = 525 gm
⇒ mass of steam which condenses = (525 - 490)gm = 35 gm
Let L = latent heat of steam
Heat lost by steam = heat gained by water + heat gained by calorimeter
35L + 35 × 1(100 - 71) = 340 × 1 × (71 - 15) + 150 × 0.1 × (71 - 15)
⇒ L = 539 cal/gm.
539 cal/gm
Mass of calorimeter and contents before passing
Steam = (150 + 340) = 490 gm.
Mass after passing steam = 525 gm
⇒ mass of steam which condenses = (525 - 490)gm = 35 gm
Let L = latent heat of steam
Heat lost by steam = heat gained by water + heat gained by calorimeter
35L + 35 × 1(100 - 71) = 340 × 1 × (71 - 15) + 150 × 0.1 × (71 - 15)
⇒ L = 539 cal/gm.
