Molecular Physics | Thermodynamics Answers

What is a Gibbs paradox? How did it arise?

Calculate the coefficient of viscosity of hydrogen at STP. Take
r = 8.90×10−2 kg m−3, l = 2×10−7m and =1.38×10−23 JK−1.

a) State the principle of equipartition of energy. Write a relation between number of
degrees of freedom, number of particles constituting the system and the total number
of constraints. Calculate the degrees of freedom for (i) single atom, (ii) diatomic
molecule.

A reversible process can only be idealised and cannot be achieved in practice.
Justify.

Write an expression for the partition function for an ideal gas made up of N
indistinguishable particles. Using this expression, obtain Sackur-Tetrode equation.

A Carnot engine has an efficiency of 40%. Its efficiency is to be raised to 50%. By
how much must the temperature of the source be increased if the sink is at 27 °C.

Define adiabatic lapse rate? Obtain an expression for adiabatic lapse rate for earth’s
atmosphere?

Using a suitable diagram, explain the most probable speed, the average speed and the root
mean square speed.

Why don't we feel cool when we are in front of sunshine, while evaporation is also taking place so rapidly?

A student wants to cool 0.25kg of Coke drink (mostly water), initially 25°C, by adding ice initially at -20°C. How much ice should be added so that the final temperature will be 0°C with all the ice melted if the heat capacity of the container may be neglected.