For which of the following reactions is $\Delta H$ approximately equal to $\Delta E$?

Fill in the blanks:
$(i)$ The process of attaining thermal equilibrium between any two heat-conducting bodies is called the $\dots\dots$ law of thermodynamics.
$(ii)$ The law of thermodynamics is actually the law of $\dots\dots$.
$(iii)$ $A$ thermometer measures temperature according to the $\dots\dots$ law of thermodynamics.

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 $kJ$)

An ideal gas is expanded from $1 \times 10^{-3} \,m^3$ to $1 \times 10^{-2} \,m^3$ against a constant external pressure of $1 \times 10^5 \,N/m^2$ at $300 \,K$. The work done is

The heat of reaction at constant pressure is given by

What will be the work done on an ideal gas enclosed in a cylinder,when it is compressed by a constant external pressure,$p_{ext}$ in a single step as shown in the figure? Explain graphically.