$A$ gas is allowed to expand against a constant external pressure of $2.5 \ bar$ from an initial volume of $2.5 \ L$ to a final volume of $4.5 \ L$. What is the amount of work done (in $J$)?

An ideal gas is compressed from $10 \ dm^3$ to $1 \ dm^3$ at a constant pressure of $2 \ bar$. Calculate the work done on the gas during compression. (in $kJ$)

$A$ given mass of gas expands reversibly from the state $A$ to the state $B$ by three paths $1, 2$ and $3$ as shown in the figure. If $w_1, w_2$ and $w_3$ respectively be the work done by the gas along three paths then:

The evaporation of water is a:

Which one among the following is the correct option for the relationship between $C_{P}$ and $C_{V}$ for one mole of an ideal gas?

Fill in the blanks given below:
$(i)$ $A$ system in which the exchange of energy between the system and the surroundings is possible but the exchange of matter is not possible is called a .......
$(ii)$ The total amount of energy, which is the sum of the internal energy of the substance and the product of its pressure and volume, is called .......
$(iii)$ The change in energy that occurs when a chemical reaction is carried out at constant pressure is called .......
$(iv)$ The process of attaining thermal equilibrium between any two heat-conducting substances is known as the ....... law of thermodynamics.