The relation between pressure exerted by an ideal gas `(p_("ideal"))` and observed pressure `(p_("real"))` is given by the equation `" " p_("ideal")=p_("real")+(an^(2))/(V^(2))`
If pressure is taken in N `m^(-2)`, number of moles in mol and volume in `m^(3)`, calculate the unit of 'a'. What will be the unit of 'a' when pressure is in atmosphere is in atmosphere and volume in `dm^(3)` ?

Explanation

`p_("ideal")=p_("real")+(an^(2))/(V^(2))" or "(an^(2))/(V^(2))=p_("ideal")-p_("real")`
If pressure is taken in N `m^(-2)`, volume in `m^(3)`, n is mol, then `" " (a.mol^(2))/(m^(6))=Nm^(-2)" or " a=N m^(4)" mol"`
If pressure is in atm and volume in `dm^(3)`, then `" " (a.mol^(2))/(dm^(6))=atm " or " a="atm" dm^(6) mol^(-2)`.