What factors decide where an element is placed in the Periodic Table?
Phosphorus is an element in Group V of the Periodic Table. Deduce the electronic configuration for a phosphide ion, $\text{P}^{3-}$.
Phosphine, $\text{PH}_3$, is a covalent compound. Draw a ‘dot-and-cross’ diagram of phosphine. Show only the outer-shell electrons.
Some properties of phosphine are given: gas at room temperature; almost insoluble in water; reacts with hydrogen chloride; has no effect on litmus paper; breaks down to hydrogen and phosphorus only when gently warmed. Describe two ways in which the properties of ammonia differ from those of phosphine.
Construct the equation for phosphine's thermal decomposition.
Describe and explain the difference in the diffusion rates of ammonia and phosphine gases at the same temperature and pressure.
Phosphine burns in oxygen to produce phosphorus(V) oxide. Is phosphorus(V) oxide an acidic, basic or amphoteric oxide? Give a reason for your answer.