State the oxidation-number change for nitrogen, N, in this reaction. from ................. to .................
Identify the element that is oxidised in this reaction.
Calculate the volume of $\text{NO}_2$ gas, at r.t.p., made when 7.40 g of $\text{Mg(NO}_3)_2$ is heated. Use these steps. • Work out the $M_r$ of $\text{Mg(NO}_3)_2$. • Work out how many moles of $\text{Mg(NO}_3)_2$ are used. • Determine how many moles of $\text{NO}_2$ are produced. • Calculate the volume of $\text{NO}_2$ gas, in $\text{cm}^3$, at r.t.p.
Complete the dot-and-cross diagram in Fig. 4.1 for the ions in magnesium oxide. Add the charges to both ions. Fig. 4.1 presents two bracketed ions: one labelled Mg with crosses, the other labelled O with dots.
Complete the dot-and-cross diagram in Fig. 4.2 for a molecule of oxygen. The inner shells have already been drawn.