Here are the solutions to the questions: g) Which element belongs to period 2 and group V. Period 2 indicates that the element has its valence electrons in the second energy shell. Group V (or Group 15) indicates that the element has 5 valence electrons. The element in Period 2, Group 15 is Nitrogen. The element is $\boxed{\text{Nitrogen (N)}}$. h) Write the electronic configuration (S and P notation) of S, V and Z. Sulfur (S): Atomic number 16. $$1s^2 2s^2 2p^6 3s^2 3p^4$$ Vanadium (V): Atomic number 23. $$1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^3$$ Z: The symbol 'Z' is not a standard chemical symbol for an element. Without further clarification, its electronic configuration cannot be determined. G) Sodium, magnesium and aluminium are metals in period 3. Write the formulae of their: Sodium forms $\text{Na}^+$ ions. Magnesium forms $\text{Mg}^{2+}$ ions. Aluminium forms $\text{Al}^{3+}$ ions. a) Hydroxides ($\text{OH}^-$) Sodium hydroxide: $\boxed{\text{NaOH}}$ Magnesium hydroxide: $\boxed{\text{Mg(OH)}_2}$ Aluminium hydroxide: $\boxed{\text{Al(OH)}_3}$ b) Sulphates ($\text{SO}_4^{2-}$) Sodium sulphate: $\boxed{\text{Na}_2\text{SO}_4}$ Magnesium sulphate: $\boxed{\text{MgSO}_4}$ Aluminium sulphate: $\boxed{\text{Al}_2(\text{SO}_4)_3}$ c) Carbonates ($\text{CO}_3^{2-}$) Sodium carbonate: $\boxed{\text{Na}_2\text{CO}_3}$ Magnesium carbonate: $\boxed{\text{MgCO}_3}$ Aluminium carbonate: $\boxed{\text{Al}_2(\text{CO}_3)_3}$ d) Hydrogen carbonates ($\text{HCO}_3^-$) Sodium hydrogen carbonate: $\boxed{\text{NaHCO}_3}$ Magnesium hydrogen carbonate: $\boxed{\text{Mg(HCO}_3)_2}$ Aluminium hydrogen carbonate: $\boxed{\text{Al(HCO}_3)_3}$ e) Nitrates ($\text{NO}_3^-$) Sodium nitrate: $\boxed{\text{NaNO}_3}$ Magnesium nitrate: $\boxed{\text{Mg(NO}_3)_2}$ Aluminium nitrate: $\boxed{\text{Al(NO}_3)_3}$ f) Phosphates ($\text{PO}_4^{3-}$) Sodium phosphate: $\boxed{\text{Na}_3\text{PO}_4}$ Magnesium phosphate: $\boxed{\text{Mg}_3(\text{PO}_4)_2}$ Aluminium phosphate: $\boxed{\text{AlPO}_4}$