GK
CHEMISTRY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Release of heat
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Absorption of heat
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Either A or B
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None of the above
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Detailed explanation-1: -There will be an absorption of heat energy in the process of melting and boiling. In condensation as well as in freezing, heat energy is released (temperature reduced) and hence the kinetic energy of molecules decreases and gas changes to liquid and solid subsequently.
Detailed explanation-2: -There is the absorption of heat energy in the processes of sublimation, melting and boiling. Whereas, in condensation, there is a release of heat energy. Q.
Detailed explanation-3: -All solids absorb heat as they melt to become liquids. The gain of heat in this endothermic process goes into changing the state, rather than changing the temperature. The molar heat of fusion (Hfus) of a substance is the heat absorbed by one mole of that substance as it is converted from a solid to a liquid.
Detailed explanation-4: -Cause for constant temperature during melting: The absorbed heat energy during melting is used to weaken the attractive forces between particles and not the kinetic energy of the particles.
Detailed explanation-5: -latent heat, energy absorbed or released by a substance during a change in its physical state (phase) that occurs without changing its temperature.