Consider the reactions given below. On the basis of these reactions find out which of the algebraic

Question

Consider the reactions given below. On the basis of these reactions find out which of the algebraic relations given in options (a) to (d) is correct?\ i) $\mathrm{C}_{(g)}+4 \mathrm{H}_{(g)} ightarrow \mathrm{CH}_{4(g)} ; \Delta_{r} H=x \mathrm{~kJ} \mathrm{~mol}^{-1}$\ ii) $\mathrm{C}_{(	ext {graphite }, s)}+2 \mathrm{H}_{2(g)} ightarrow \mathrm{CH}_{4(g)} ; \Delta_{r} H=y \mathrm{~kJ} \mathrm{~mol}^{-1}$\

Professor PC Thomas Classes · Answer

(c) : In eqn (i), no bond is being broken while in eqn (ii), $2 \mathrm{H}-\mathrm{H}$ bonds are broken. So, in eqn (ii) some of the energy is used up to break the bonds. Thus, $x>y$.