Question

For n moles of gas Vander waal's equation is
$(P-\frac{a}{V^2})(V-b)=nRT$
Find the dimensions of a and b, where P is gas pressure, V = volume of gas T = temperature of gas

Answer 1

Dimension of $P=$ Dimension of $\frac{a}{V^2}$

$\therefore$Dimension of $a=\left[P\right]\left[V^2\right]$

$a=M{L}^{-1}{T}^{-2}{\left(L^3\right)}^2$

$a=M{L}^5{T}^{-2}$

Dimension of $b=$Dimension of $V=M^0{L}^3{T}^0$