Which one of the following equations does not correctly represent the first law of thermodynamics for the given processes involving an ideal gas? (Assume non-expansion work is zero)

For silver, C_p(J K^–1 mol^–1) = 23 +0.01 T. If the temperature (T) of 3 moles of silver is raised from 300 K to 1000 K at 1 atm pressure, the value of $$\Delta H$$ will be close to :

Given

(i)  C (graphite) + O₂(g) $$ \to $$ CO₂(g); $$\Delta $$rH$$^\Theta $$ = x kJ mol^$$-$$1

(ii)  C(graphite) + $${1 \over 2}$$O₂(g) $$ \to $$ CO(g); $$\Delta $$rH$$^\Theta $$ = y kJ mol^$$-$$1

(iii)  CO(g) + $${1 \over 2}$$ O₂(g) $$ \to $$ CO₂(g); $$\Delta $$rH$$^\Theta $$ = z kJ mol^$$-$$1

Based on the above thermochemical equations, find out which one of the following algebraic relationships is correct?

The combination of plots which does not represent isothermal expansion of an ideal gas is –