
The volume thermal expansion coefficient of an ideal gas at constant pressure is

Important Questions on Heat and Temperature


An air bubble starts rising from the bottom of a lake. Its diameter is at the bottom and at the surface. The depth of the lake is and the temperature at the surface is . What is the temperature at the bottom of the lake? Assume that the variation of density of water with depth is negligible. Atmospheric pressure is of and .


The volume of a certain mass of gas at constant pressure increases from litre to litre due to an increase of temperature from to . From these data, find the value of absolute zero.

The volume occupied by a certain mass of gas at and of mercury pressure is . If the temperature be changed to and pressure to of mercury, what would be the volume of the gas?

An air bubble gradually rises from a depth of in a lake where the temperature is to the surface where the temperature is . Compare the radii of the bubble in the two places. Atmospheric pressure of and density of mercury .


Represent the union of two sets by Venn diagram for each of the following.
is a prime number between and
is an odd number between and

A gas expands in such a manner that its pressure and volume comply the condition constant. Find out whether the gas is heated or cooled during such an expansion.


The measurement of a room is . If the temperature of the room increases from in the morning to at noon, calculate what percentage of the air will be expelled from the room, pressure remaining constant.

A glass vessel contains air at . To what temperature must it be heated to expel th of the air, pressure remaining constant?

The volume of a gas is doubled by changing its temperature at constant pressure. The initial temperature of the gas was . Calculate the final temperature.

A vessel of volume contains an ideal gas at . After a portion has escaped from the vessel, the pressure decreases by atmosphere (temperature remaining constant). Find the mass of the gas escaped. The density under normal conditions .


A capillary glass tube with fine bore has both the ends sealed and a small mercury pellet inside. The pellet divides the tube into two parts whose lengths are in the ratio of . If the initial temperature of the whole arrangement is and if it is heated afterwards to what will be the change in the air pressure inside the tube?

A bulb of volume is connected to another bulb of volume by a narrow tube of negligible volume. The two bulbs were initially at the same temperature and pressure . Now is heated to a temperature . Find the new pressure and show the fraction of the original mass of air that stays in the bulb is.



