Calculate the standard enthalpy of combustion of carbon monoxide if
$\Delta_f H^\circ (\text{CO}) = -110 \text{ kJ mol}^{-1}$
$\Delta_f H^\circ (\text{CO}_2) = -393 \text{ kJ mol}^{-1}$

Which of the following processes is an endothermic ?

The solubility of sapringly soluble salt $\text{AB}_2$ is $18 \cdot 78 \times 10^{-4} \text{ g/dm}^3$ What is its solubility product ? (Molar mass of $\text{AB}_2 = 187 \cdot 8 \text{ g mol}^{-1}$)

What is the pH of resulting solution when $20 \text{ mL } \dfrac{M}{10} \text{ NaOH}$ and $10 \text{ mL } \dfrac{M}{10} \text{ H}_2\text{SO}_4$ are mixed together ?