EASY
Earn 100

Calculate the volume occupied by 0.845 moles moles of nitrogen gas at a pressure of 1.37 atm and a temperature of 315 K. Given R=0.0821 LK-1mol

Important Questions on Thermal Expansion

MEDIUM
An empty bottle is corked when the air inside it is at 10°C and the barometer reads 0.75 m of Hg. If the cork blows out when the pressure inside the bottle exceeds the atmospheric pressure by 1.00 m of Hg, calculate the temperature at which the bottle must be heated to blow the cork. Assume that the volume of the bottle remains constant when heated.
HARD

The volume of a certain mass of gas at constant pressure increases from 1 litre to 1.128 litre due to an increase of temperature from 0°C to 35°C. From these data, find the value of absolute zero.

EASY
Which one is the correct value of Boltzmann constant.
EASY

The volume occupied by a certain mass of gas at 27°C and 740 mm of mercury pressure is 400 cm3. If the temperature be changed to 0°C and pressure to 760 mm of mercury, what would be the volume of the gas?

HARD

The measurement of a room is 15 m×12 m×8 m. If the temperature of the room increases from 22°C in the morning to 30°C at noon, calculate what percentage of the air will be expelled from the room, pressure remaining constant.

HARD

An air bubble gradually rises from a depth of 10 m in a lake where the temperature is 10°C to the surface where the temperature is 25°C. Compare the radii of the bubble in the two places. Atmospheric pressure =75 cm of Hg and density of mercury =13.6 g cm3.

HARD

An air bubble starts rising from the bottom of a lake. Its diameter is 3.6 mm at the bottom and 4 mm at the surface. The depth of the lake is 2.5 m and the temperature at the surface is 40°C. 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 76 cm of Hg and g=980 cm s2.

MEDIUM
A hypothetical atom has energy levels uniformly separated by 1.2 eV. At a temperature of 2000 K, what is the ratio of the number of atoms in the 13th excited state to the number in the 11th excited state?
MEDIUM

A gas expands in such a manner that its pressure and volume comply the condition pV2= constant. Find out whether the gas is heated or cooled during such an expansion.

EASY
Which one is the correct dimensional formula for Boltzmann constant?
EASY

A glass vessel contains air at 42°C. To what temperature must it be heated to expel 14th of the air, pressure remaining constant?

EASY

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 3:1. If the initial temperature of the whole arrangement is 0°C and if it is heated afterwards to 273°C what will be the change in the air pressure inside the tube?

EASY

The volume of a gas is doubled by changing its temperature at constant pressure. The initial temperature of the gas was 13°C. Calculate the final temperature.

HARD

A vessel of volume V=0.03 m3 contains an ideal gas at 0°C. After a portion has escaped from the vessel, the pressure decreases by P=0.78 atmosphere (temperature remaining constant). Find the mass of the gas escaped. The density under normal conditions ρ0=1.3 kg m3.

HARD

A bulb A of volume V1 is connected to another bulb B of volume V2 by a narrow tube of negligible volume. The two bulbs were initially at the same temperature T1 and pressure p1. Now A is heated to a temperature T2. Find the new pressure P2 and show the fraction of the original mass of air that stays in the bulb A is.

EASY
Why do the tyres of a car filled with compressed air become slightly flat in winter?
EASY
Calculate the value of Boltzmann constant k. Given: R=8.3×103 J(kmol)-1K-1 and Avogadro number N=6.023×1026 (kmol)-1.
HARD

At what depth in a lake will a bubble of air have one-half the volume it will have on reaching the surface? The height of the barometer at that time is 0.76 m of mercury and density of mercury 13.6×103 kg m3.

EASY

A cylinder contains a perfect gas at a temperature of 20°C and a pressure of 15 atmosphere in a volume of 100 litre. A piston is lowered into the cylinder decreasing the volume occupied by the gas to 80 litre and raising the temperature to 25°C. What is the gas pressure now?