State and explain the trend in ionisation energy down Group 2.
State and explain the trend in melting point down Group 17.
The melting point falls down Group 2. Explain this trend.
A number of reactions involving the Group 2 metal barium, $\text{Ba}$, are shown. $\text{Ba(NO}_3)_2(aq) + \text{H}_2(g) \xleftarrow{\text{reaction 1}} \text{Ba}(s) \xrightarrow{\text{reaction 2}} \text{Ba(OH)}_2(aq) + \text{H}_2(g)$ (State the reagent needed for each of reactions 1 and 2.)
Name $X$ and write an equation for its formation. ($X(s)$ is produced when barium is heated in air.)
The $\text{Ba(NO}_3)_2(aq)$, formed in reaction 1, is heated to dryness. The anhydrous solid is then heated strongly and breaks down. Barium oxide is produced, together with two other products. Identify the two other products of this decomposition reaction and state what would be observed.
State what would be observed on adding excess $\text{MgSO}_4(aq)$ to the $\text{Ba(OH)}_2(aq)$ produced in reaction 2. Explain your answer.