What products are obtained when beryllium oxide is treated separately with aq. HCl and aq. NaOH solutions respectively?

Calculate internal energy change of a system if work done by the system is 8 J and heat supplied to it is 40 J .

Identify basic oxide from following.

Calculate the solubility product of sparingly soluble salt BA at $27^{\circ} \mathrm{C}$ if its solubility is $1.8 \times 10^{-5} \mathrm{~mol} \mathrm{dm}^{-3}$ at same temperature.