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The amount of heat which is used to change the state of matter not for increase the temperature is called

• Latent heat

• Specific heat

• Heat capacity

• None of the above.

Which of the following will produce severe burns ?

• Cold water

• Hot water

• Boiling water

• Steam

Ice floats on water because

• it has higher density than water

• it has lower density than water due to more volume

• it is solid

• it is low melting solid

Latent heat of fusion is amount of

• heat energy required to change 1 kg solid into liquid completely at its melting point.

• heat energy required to convert 1 kg solid into liquid at room temperature

• heat energy required to change 1 g of solid into liquid completely

• heat energy required to change 1 kg of solid into liquid at any temperature.

When heat is constantly supplied by a burner to boiling water, then the temperature of water during vapourisation

• Rises very slowly

• Rises rapidly until steam is produced

• First rises and then becomes constant

• Does not rise at all

When water at 0°C freezes to form ice at the same temperature of 0°C, then it

• Absorbs some heat

• Releases some heat

• Neither absorbs nor releases heat

• Absorbs exactly 3.34 x 10⁵J/kg of heat

A student heats a beaker containing ice and water. He measures the temperature of the content of the beaker as a function of time. Which of the following will correctly represent the result.

• 
• 
• 
• 

In which form, do the water molecules have less kinetic

energy?

• (a) Ice

• (b) Water

• (c) Steam

• (d) All of them have equal kinetic energy

Which of the following has highest kinetic energy?

• (a) Particles of ice at 0 degree C

• (b) Particles of water at 0 degree C

• (c) Particles of water at 100 degree C

• (d) Particles of steam at 100 degree C

235K = _________°C

• 38

• -20

• 20

• -38