The apparent coefficient of expansion of a liquid when heated in a copper vessel is C and when heated in a silver vessel, it is S. If A is the linear coefficient of expansion of copper, then the linear coefficient of expansion of silver is

γr=γa+γv, where γr= coefficient of real expansion,γα = coefficient of apparent expansionand γv = coefficient of expansion of vessel.For copper, γr = C + 3αCu= C + 3AFor silver,    γr = S + 3αAg⇒         C + 3A = S + 3αAg⇒           αAg = C - S + 3A3