Heat and Thermodynamics 1 Question 2

2. A thermally insulated vessel contains 150g of water at 0C. Then, the air from the vessel is pumped out adiabatically. A fraction of water turns into ice and the rest evaporates at 0C itself. The mass of evaporated water will be closest to

(Latent heat of vaporisation of water =2.10×106Jkg1 and latent heat of fusion of water =3.36×105Jkg1 )

(2019 Main, 8 April I)

(a) 150g

(b) 20g

(c) 130g

(d) 35g

Show Answer

Solution:

  1. Let x grams of water is evaporated.

According to the principle of calorimetry,

Heat lost by freezing water (that turns into ice) = Heat gained by evaporated water Given, mass of water =150g

(150x)×103×3.36×105=x×103×2.10×106(150x)×3.36=21xx=1507.25=20.6x20g



जेईई के लिए मॉक टेस्ट

एनसीईआरटी अध्याय वीडियो समाधान

दोहरा फलक