Q.

An amount of ice of mass 103 kg and temperature –10°C is transformed to vapour of temperature 110°C by applying heat. The total amount of work required for this conversion is, (Take, specific heat of ice = 2100 J kg1 K1, specific heat of water = 4180 J kg1 K1, specific heat of steam = 1920 J kg1 K1, Latent heat of ice = 3.35×105 J kg1 and Latent heat of steam = 2.25×106 J kg1)          [2025]

1

3022 J

 

2

3043 J

 

3

3003 J

 

4

3024 J

 


Ans.

(2)

First, Ice at –10°C Q1 Ice at 0°C Q2 Water at 0°C. Then, Water at 0°C Q3 Water at 100°C Q4 Vapour at 100°C Q5 Vapour at 110°C

Q1=m×SI×T=103×2100×10=21 J

Q2=m×Lf=103×3.35×105=335 J

Q3=m×Sw×T=103×4180×100=418 J

Q4=m×Lv=103×2.25×106=2250 J

Q5=m×Sv×T=103×1920×10=19.2 J

Qnet=3043.2 J