Physics [1 Mark Question Answer]

Boiling point : The particular temperature at which vaporization occurs is called the boiling point of liquid .

Boiling : The change from liquid to gaseous phase on heating at a constant temperature is called boiling.

Average kinetic energy does not change.

As their id no change in temperature the average kinetic energy of the molecules does not change.

1 g of water at 0°C has more heat than 1 g of ice at 0°C. This is because ice at 0°C absorbs 360 J of heat energy to convert into water at 0°C.

Latent heat of melting.

Latent heat is absorbed by ice.

Melting.

It means 1 g of ice at 0°C absorbs 360 J of heat energy to convert into water at 0°C.

This is because at high altitudes atmospheric pressure is low; therefore, boiling point of water decreases and so it does not provide the required heat energy for cooking.

In a pressure cooker, the water boils at about 120°C to 125°C.

Latent heat

Yes, the substance absorbs or liberates heat during the change of phase.

The boiling point of a liquid increases on increasing the pressure.

There is no change in temperature during the change of phase.

The boiling point of water increases on adding salt .

The process of change from one state to another at a constant temperature is called the change of phase of substance.

Volume of water wills increases when it boils at 100oC.

The measurement of the quantity of heat is called calorimetry.

One kilo-calorie of heat is the heat energy required to raise the temperature of 1 kg of water from 14.5oC to 15.5oC.

S.I. unit of heat is joule (symbol J).

By polishing the outer and inner surface of the vessel the loss due to radiation can be minimised.

Heat capacity of the calorimeter should be low so out of three metals the one which have lowet specific heat capacity should be preferred.

A calorimeter is a cylindrical vessel which is used to measure the amount of heat gained or lost by a body when it is mixed with other body.

To avoid freezing of wine and juice bottles.

Radiator in car.

The kinetic energy due to random motion of the molecules of a substance is known as its heat energy.

Change in temperature and the nature of material

Water has the highest specific heat capacity.