Limiting value of equivalent conductance of BaSO₄, BaCl₂ and H₂SO₄ are X, Y and Z respectively.

Equivalent conductance of HCI at infinite dilution is

The reaction is : 

H₂SO₄​ + BaCl₂​ ⟶ 2HCl + BaSO₄ 

So, The equivalent conductance of HCl at infinite dilution is 

  = $[ {( {\mathrm{\lambda }}_{\mathrm{eq}}^{°} )}_{{\mathrm{BaCl}}_2}+ {( {\mathrm{\lambda }}_{\mathrm{eq}}^{°} )}_{{\mathrm{H}}_2{\mathrm{SO}}_4} - {( {\mathrm{\lambda }}_{\mathrm{eq}}^{°} )}_{{\mathrm{BaSO}}_4} ]$ 

  = $\frac{1}{2}$( Y + Z - X )