If  $S+O_2\to S{O}_2;\Delta H=-298.2KJ$
$S{O}_2+\frac{1}{2}{O}_2\to S{O}_3;\Delta H=-98.7KJ$ 
$S{O}_3+H_{2}O\to H_{2}S{O}_4;\Delta H=-130.2KJ$ 
$H_2+\frac{1}{2}{O}_2\to H_{2}O;\Delta H=-227.3KJ$ 
The enthalpy of formation of $H_{2}S{O}_4$  will be