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प्रश्न
1 g ice of 0℃ melts to form 1 g water at 0℃. State whether the latent heat is absorbed or given out by ice.
उत्तर
Ice turns into water when it absorbs latent heat.
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संबंधित प्रश्न
Write the approximate value of specific latent heat of ice.
- Which requires more heat: 1 g ice at 0℃ or 1 g water at 0℃ to raise its temperature to 10℃?
- Explain your answer in part (a).
Explain the following:
The surrounding become pleasantly warm when water in a lake starts freezing in cold countries.
During transformation of liquid phase to solid phase, the latent heat is ______.
Liquid ammonia is used in ice factory for making ice from water. If water at 20°C is to be converted into 2 kg ice at 0°C, how many grams of ammonia are to be evaporated? (Given: The latent heat of vaporization of ammonia = 341 cal/g)
A thermally insulated pot has 150 g ice at temperature 0°C. How much steam of 100°C has to be mixed to it, so that water of temperature 50°C will be obtained? (Given : latent heat of melting of ice = 80 cal/g, latent heat of vaporization of water = 540 cal/g, specific heat of water = 1 cal/g °C)
Explain the following temperature vs time graph.
Why does weather become pleasant when it starts freezing in cold countries?
Define the term ‘specific latent heat of fusion’ of a substance.
State two advantages of the high specific latent heat capacity of steam, which is about 226 × 104 J/kg?
Derive an expression for the amount of heat given out or taken up, when its temperature falls or rises by t°C.
What observation you will record and how will you determine the specific latent heat of fusion of ice?
Calculate the total amount of heat required to convert 100g ice at 0°C to steam at 100°C.
(Specific latent heat of fusion of ice = 336 J/g, specific latent heat of vaporization of steam = 2260 J/g, specific heat capacity of water = 4.2 J/g°C).
1 kg of water is contained in a 1.25 kW kettle. Assuming specific heat capacity of water = 4.2 J/g °C and specific latent heat of vaporization = 2260 J/g, calculate:
(i) the time taken for the temperature of water to rise from 25°C to its boiling point,
(ii) the mass of water which evaporates per minute from the boiling water.
Match the columns.
| Column A | Column B |
| 1) Specific latent heat of fusion | a) Air saturated with vapour |
| 2) Specific latent heat of vaporisation | b) Solid converts into liquid |
| 3) Dew point temperature | c) liquid converts into gas |
Write the name.
The phase in which solid substances are converted into liquid.
Write scientific reason.
Use a pressure cooker to cook food in cold air.
