1.
Consider the following processes:

12AB\frac{1}{2}A \rightarrow B; ΔH=+150kJ mol1\Delta H = +150\,\text{kJ mol}^{-1}

3B2C+D3B \rightarrow 2C + D; ΔH=125kJ mol1\Delta H = -125\,\text{kJ mol}^{-1}

E+A2DE + A \rightarrow 2D; ΔH=+350kJ mol1\Delta H = +350\,\text{kJ mol}^{-1}

For B+DE+2CB + D \rightarrow E + 2C, ΔH\Delta H will be: