Chemistry 9701 · AS & A Level · The Periodic Table: chemical periodicity
The Periodic Table: chemical periodicity — practice question
D, E, F, and G form four successive elements in the fourth period of the Periodic Table. (The letters are not the real symbols of the elements.) D is a soft, shiny metal whose melting point is a little higher than room temperature. Its amphoteric oxide, $\text{D}_2\text{O}_3$, has a melting point of $1900^\circ\text{C}$ and may be obtained by heating D in oxygen. G is a solid that occurs in several allotropes, most of which consist of $\text{G}_8$ molecules. G burns in air to form $\text{GO}_2$, which dissolves in water to give an acidic solution. This solution reacts with sodium hydroxide to produce the salt $\text{Na}_2\text{GO}_3$.
(a)[1]
Suggest what D and G are.
(b(i))[2]
Write an equation for how $\text{D}_2\text{O}_3$ reacts with hydrochloric acid.
(b(ii))[2]
Write an equation for how $\text{D}_2\text{O}_3$ reacts with sodium hydroxide.
(c)[1]
Suggest the bonding type and structure present in $\text{D}_2\text{O}_3$.
(d)[1]
Write an equation for how an acidic solution forms when $\text{GO}_2$ dissolves in water.
Worked solution & mark scheme
This 7-mark question has a full step-by-step worked solution and mark scheme. One marking point: “D = Ga and G = Se” …