(a)[3]
Finish the dot-and-cross diagram below to show the bonding in ammonium chloride. For each of the six atoms, show every electron in its outer shell. Three electrons have already been drawn. Use the following code for your electrons: electrons from chlorine, electrons from hydrogen, electrons from nitrogen.
(b(i))[1]
Suggest why concentrated $\text{H}_2\text{SO}_4$, the usual drying agent for gases, is not suitable for ammonia.
(b(ii))[1]
Write the equation for the reaction of $\text{CaO}$ with $\text{H}_2\text{O}$.
(b(iii))[1]
Suggest why $\text{CaO}$ is used instead of $\text{MgO}$ to dry ammonia.
(c(i))[2]
Write the equation for the thermal decomposition of calcium nitrate, $\text{Ca(NO}_3)_2$.
(c(ii))[2]
State and explain the way the thermal stabilities of the nitrates change down Group II.