Advertisements
Advertisements
प्रश्न
Numerical Problem.
How much heat energy is required to change 2 kg of ice at 0°C into water at 20°C? (Specific latent heat of fusion of water = 3,34,000 J/kg, Specific heat capacity of water = 4200 JKg–1K–1).
Advertisements
उत्तर
Total heat = Heat required to convert 2Kg of ice into water at 0°C + Heat required to convert 2Kg of water at 0°C to 2Kg of water at 20°C
Heat = m (hfw) + mc∆T
Here, m(mass of ice) = 2Kg
hfw (specific latent heat of water) = 3,34,000J/Kg
C (specific heat capacity of water) = 4200JKg– 1K– 1
AT (Temperature difference) = 20°C
Therefore, Heat required = (2 × 334000) + (2 × 4200) (20 – 0)
= 668000 + 8400 (20)
= 668000+ 168000
Heat required = 8,36,000 J
APPEARS IN
संबंधित प्रश्न
Give a mathematical relation between Heat Capacity and Specific Heat Capacity.
The global warming has resulted:
(a) the increase in yield of crops
(b) the decrease in sea levels
(c) the decrease in human deaths
(d) the increase in sea levels
Figure shows a paddle wheel coupled to a mass of 12 kg through fixed frictionless pulleys. The paddle is immersed in a liquid of heat capacity 4200 J K−1 kept in an adiabatic container. Consider a time interval in which the 12 kg block falls slowly through 70 cm. (a) How much heat is given to the liquid? (b) How much work is done on the liquid? (c) Calculate the rise in the temperature of the liquid neglecting the heat capacity of the container and the paddle.
Give one example where high specific heat capacity of water is used as cooling.
What are other units of heat? Name and define them.
For a gas, `"R"/"C"_"v"=0.4`, where R Is universal gas constant and Cv is the molar specific heat at constant volume. The gas is made up of molecules, which are ______
Which of the following substances (A, B and C) has the highest specific beat?
The ratio of the specific heats `c_"p"/c_"v"=gamma` in terms of degrees of freedom 'n' is given by ______.
Match the following:
| Column A | Column B | ||
| 1. | Specific heat capacity of water | a. | 0°C |
| 2. | Latent heat of fusion of ice | b. | 2260 J/g |
| 3. | Latent heat of vaporization of water | c. | 100°C |
| 4. | The melting point of iced | d. | 4.2 J/g°C |
| 5. | The boiling point of water | e. | 336 J/g |
Prove the Mayer's relation `C_p - C _v = R/J`
