The equation of state of a gas is given by (P+aT2V)Vc=(RT+b), where a, b, c and R are constants. The isotherms can be represented by P=AVm−BVn , where A and B depend only on temperature and
(P+aT2V)Vc=RT+bP+aT2V=RTVc+bVcP=(RT+b)V−c−aT2V−1Comparing withP=AVm−BVnm=−c; n=−1