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Which of the following statements about latent heat for a given substance is/are correct? 1. It is fixed at a given temperature 2. It depends upon temperature and volume 3. It is independent of temperature and volume 4. It depends on the temperature but independent of volume

Which of the following statements about latent heat for a given substance is/are correct? 1. It is fixed at a given temperature 2. It depends upon temperature and volume 3. It is independent of temperature and volume 4. It depends on the temperature but independent of volume Correct Answer 1 and 3

CONCEPT

  • Latent Heat: The amount of heat required per mass to change the state of any substance. It is a hidden form of heat.
  • The change in state always occurs at a constant temperature.
  • The SI unit of latent heat is Joule/kg

 

  • Latent heat of fusion and vaporization:
  • In the process of melting or vaporization, the temperature remains constant. The amount of heat needed to change the state of matter having mass m is-
  • Q = m L

 

  • Latent heat of fusion: It is the heat required for 1 kg of substance to change it from solid to liquid state without change of temperature.
  • Latent heat of fusion of ice = 3.36 × 105 J/kg
  • In CGS = 80 cal / gm.

 

  • Latent heat of Vaporization: It is the heat required for 1 kg of substance to change it from liquid to gaseous state without change of temperature.
  • Latent heat of vaporization of water = 2.25 × 106 J/kg.
  • In CGS = 536 cal / gm


EXPLANATION

The latent heat is hidden heat for change in state.

In the process of change of state temperature remains constant.

⇒ Latent heat is fixed at a given temperature, thus independent of temperature

The volume of the object while changing the state is fixed.

⇒ Latent heat is independent of volume.

∴ Statement 1and 3 are true ⇒ Option 2 is correct.

Related Questions

Which of the following statement(s) about latent heat for a given substance is/are correct?
1. It is fixed at a given temperature.
2. It depends upon the temperature and volume.
3. It is independent of temperature and volume.
4. It depends on the temperature but independent of volume.
Which of the following is true about the Latent heat? a. It is an amount of heat absorbed by a unit mass of the substance to change its state. b. Temperature changes due to absorption of heat. c. S.I. unit of Latent heat is Joules per kilogram. d. Latent heat is used up in overcoming the force of attraction between the molecules of the substance.
Consider the following statements: 1. The entropy of a pure crystalline substance at absolute zero temperature is zero. 2. the efficiency of a reversible heat engine is independent of the nature of the working substance and depends only on the temperature of the reservoirs between which it operates.  3. Carnot’s theorem states that of all heat engines operating between a given constant temperature source and a given constant temperature sink, none has a higher efficiency than a reversible engine Which of the above statements are correct?
Consider the following statements.
1. Steam at 100°C and boiling water at 100°C contain same amount of heat.
2. Latent heat of fusion of ice is equal to the latent heat of vaporization of water.
3. In an air conditioner, heat is extracted from the room air at the evaporator coils and is ejected out at the condensor coils.
Which of these statements is/are correct?
In a surface condenser, the water flowing through a series of tubes at the rate of 200 kg/hr is heated from 15 degree Celsius to 75 degree Celsius. The steam condenses on the outside surface of tubes at atmospheric pressure and the overall heat transfer coefficient is estimated at 860 k J/m2 hr degree. Find the effectiveness of the heat exchanger. At the condensing pressure, stream has a saturation temperature 0f 100 degree Celsius and the latent heat of vaporization is 2160 k J/kg. Further, the steam is initially just saturated and the condensate leaves the exchanger without sub-cooling i.e. only latent heat of condensing steam is transferred to the water. Take specific heat of water as 4 k J/kg K
In a surface condenser, the water flowing through a series of tubes at the rate of 200 kg/hr is heated from 15 degree Celsius to 75 degree Celsius. The steam condenses on the outside surface of tubes at atmospheric pressure and the overall heat transfer coefficient is estimated at 860 k J/m2 hr degree. Find the number of transfer units of the heat exchanger. At the condensing pressure, stream has saturation temperature 0f 100 degree Celsius and the latent heat of vaporization is 2160 k J/kg. Further, the steam is initially just saturated and the condensate leaves the exchanger without sub-cooling i.e. only latent heat of condensing steam is transferred to water. Take specific heat of water as 4 k J/kg K
In pure metals solidification is controlled by the rate at which the latent heat of solidification can be conducted away from the solid/liquid interface. Which among the following equation satisfies the heat flow and the interface stability? (Kl, Ks are respective thermal conductivities of liquids and solids, L the latent heat of fusion per unit volume, v growth rate).
Which of the following option is correct about the Latent heat of vaporization? Once the water has begun to boil, the temperature remains constant at 100°C until all the water has changed into steam. The burns caused by steam are much more severe than those caused by boiling water. This is because steam contains more heat, in the form of latent heat than boiling water.
Consider the following statements regarding heat waves in India.  I. Heat waves mostly occur over Rajasthan, Punjab and Haryana towards the end of April but they mainly take place in May.  II. Any heat wave lasts for around 4-5 days.  III. If there is an increase in temperature by 6-7 degrees Celsius above normal, that is known as the Moderate Heat Wave whereas if it is 8 degree Celsius or more, that is known as Severe heat wave.  Which among the above statements is/are correct regarding the heat waves?
The graph given above indicates change in temperature (θ) when heat (Q) was given to a substance. Which among the following parts of the graph correctly depict the latent heat of the substance?