Calorimetry

Q. In an industrial process 10 kg of water per hour is to be heated from ${20}^{\circ }Cto{80}^{\circ }C.$ To do this steam at ${150}^{\circ }C$ is
passed from a boiler into a copper coil immersed in water. The steam condenses in the coil and is returned to
the boiler as water at ${90}^{\circ }C.$ how many kg of steam is required per hour.
(Specific heat of steam = 1 calorie per gm°C, Latent heat of vaporization = 540 cal/gm)

1. 1 gm
2. 1 kg
3. 10 gm
4. 10 kg

Q.

Heat required to convert one gram of ice at $0^{\circ }C$ into steam at ${100}^{\circ }C$ is (given $L_{stream}$ = 536 cal/gm)

1. 1 kilo calorie

2. 100 calorie

3. 0.01 kilo calorie

4. 716 calorie

Q. How much heat energy is gained when $5kg$ of water at ${20}^{\circ }C$ is brought to its boiling point?
$(\text{Specific heat of water}=4.2kJk{g}^{-1}{c}^{-1})$

1. $1680kJ$

2. $1700kJ$

3. $1720kJ$

4. $1740kJ$

Q. A block of ice at - ${10}^{\circ }C$ is slowly heated and converted to steam at ${100}^{\circ }C$. Which of the following curves represent the phenomenon qualitatively?

1. 
2. 
3. 
4. 

Q.

Steam at ${100}^{\circ }C$ is passed into 1.1 kg of water contained in a calorimeter of water equivalent 0.02 kg at ${15}^{\circ }C$ till the temperature of the calorimeter and its contents rises to ${80}^{\circ }C$. The mass of the steam condensed in kg is

1. 0.130

2. 0.065

3. 0.260

4. 0.135

Q. When 300 J of heat is added to 25 gm of sample of a material its temperature rises from ${25}^{\circ }Cto{45}^{\circ }C.$ the thermal capacity of the sample and specific heat of the material are respectively given by

1. $600J{/}^{\circ }C,15J/k{g}^{\circ }C$
2. $150J{/}^{\circ }C,60J/k{g}^{\circ }C$
3. $Noneofthese$
4. $15J{/}^{\circ }C,600J/k{g}^{\circ }C$

Q. A calorimeter contains 0.2kg of water at ${30}^{\circ }C.$ 0.1 kg of water at ${60}^{\circ }C$ is added to it, the mixture is well stirred
and the resulting temperature is found to be ${35}^{\circ }C.$ The thermal capacity of the calorimeter is

1. 6300 J/K
2. 1260 J/K
3. 4200 J/K
4. None of these

Q. A lump of ice (0.1 kg) at $-{10}^{\circ }$C is put in 0.15 kg of water at ${20}^{\circ }$C. How much water will be found in the mixture when it has reached thermal equilibrium?
$(C_{ice}=0.5kcalk{g}^{-1}{k}^{-1},L_{ice}=80kcalk{g}^{-1})$

1. 31.25 g
2. 150 g
3. 210 g
4. 181.25 g

Q. An electrically heating coil was placed in a calorimeter containing 360 gm of water at ${10}^{\circ }C$. The coil consumes energy at the rate of 90 watt. The water equivalent of the calorimeter and the coil is 40 gm. Calculate, what will be the temperature of the water after 10 minutes.
(J = 4.2 Joule/cal.)

1. ${22.14}^{\circ }C$
2. ${42.14}^{\circ }C$
3. ${142.14}^{\circ }C$
4. ${420.14}^{\circ }C$

Q. Work done in converting one gram of ice at $–{10}^{\circ }C$ into steam at ${100}^{\circ }C$ is

1. 3045 J
2. 6056 J
3. 721 J
4. 616 J