Give $\Delta$ H_r Values for Each of the Following Reactions from the from the Information

Essay

Give $\Delta$ H_r values for each of the following reactions from the information below.
$\Delta$ H_f ^$\omicron$ (HCl(g))= -92.31 kJ.mol^-1
H-Cl bond enthalpy = +431 kJ.mol^-1
O-H bond enthalpy = +463 kJ.mol^-1
$\Delta$ H_f ^$\omicron$ (H₂O(g))= -241.8 kJ.mol^-1
(a)2H(g)+ O(g) $\rightarrow$ H₂O(g)
(b)H₂(g)+ Cl₂(g) $\rightarrow$ 2HCl(g)
(c)H(g)+ Cl(g) $\rightarrow$ HCl(g)