One kilogram of ice at $0°$C is mixed with one kilogram of water at 80$°C$. The final temperature of the mixture is (Take: Specific heat of water = 4200 J $k{g}^{-1}{C}^{-1}$, Latent heat of ice = 336 kJ $k{g}^{-1}$)

1. $0°$C
2. $50°C$
3. $40°C$
4. $60°C$

Heat capacity is equal to the product of:

1.  mass and gas constant

2.  mass and specific heat

3.  latent heat and volume of water

4.  mass and Avogadro number

Two identical bodies are made of a material for which the heat capacity increases with temperature. One of these is at ${100}^{°}$ C, while the other one is at $0^{° }$C. If the two bodies are brought into contact, then assuming no heat loss, the final common temperature is -

1. ${50}^{°} C$

2. more than ${50}^{°}$C

3. less than ${50}^{°}$C but greater than $0^{°}$C

4.  $0 {}_{0}C$

Steam at 100°C is passed into 20 g of water at 10°C. When water acquires a temperature of 80°C, the mass of water present will be (Take specific heat of water=1 cal g^-1 °C^-1 and latent heat of steam = 540 cal g^-1)

1. 24 g                       

2. 31.5g

3. 42.5 g                   

4. 22.5 g

Liquid oxygen at 50K is heated to 300K at constant pressure of 1 atm. The rate of heating is constant Which one of the following graphs represents the variation of temperature with time?
1. 
2. 
3. 
4. 

When 1 kg of ice at $0°\mathrm{C}$ melts to water at $0°\mathrm{C}$, the resulting change in its entropy, taking latent heat of ice to be $80 \mathrm{cal}/\mathrm{g},$ is

1.  $8\times {10}^4 \mathrm{cal}/\mathrm{K}$                                     

2.  $80 \mathrm{cal}/\mathrm{K}$

3.  $293 \mathrm{cal}/\mathrm{K}$                                         

4.  $273 \mathrm{cal}/\mathrm{K}$

The vapour of a substance behaves as a gas :

1. Below the critical temperature                     

2. Above the critical temperature

3. At 100°C                                               

4. At 1000°C

The temperature below which gas should be cooled, before it can be liquified by pressure only is termed as :

1. The dew point                           

2. The freezing point

3. The saturation point                   

4. The critical point

The change in volume V with respect to an increase in pressure P has been shown in the figure for a non-ideal gas at four different temperatures ${\mathrm{T}}_1, {\mathrm{T}}_2,{\mathrm{T}}_3$ and ${\mathrm{T}}_4$ . The critical temperature of the gas is

1. ${\mathrm{T}}_1$                                 

2. ${\mathrm{T}}_2$

3. ${\mathrm{T}}_3$                                 

4. ${\mathrm{T}}_4$

In the adjoining figure, various isothermals are shown for a real gas. Then: