Discuss the general characteristics and gradation in properties of alkaline earth metals.

Explanation

Atomic size increases from top to bottom in the group due to increase in the number of orbits.
(2) Densities increase from top to bottom in the group but Ca is less denser than Mg.
(3) M.pts and b.pts do not vary regularly.
(4) Ionisation enthalpies decrease from top to bottom.
(5) Hydration enthalpies decrease from top to bottom in the group.
(6) Reactivity toward air and water increases form top to bottom in the group. All these elements burn in air forming metal oxides and metal nitrides. Be and Mg do not react with water but other elements react with water and the reactivity increases from Ca to Ba.
(7) All these elements react with halogens forming halides.
(8) All these elements except beryllium react with hydrogen directly forming ionic hydrides.
(9) These elements readily reacts with acids liberating hydrogen.
(10) Alkaline earth metals are good reducing agents and their reduction power increases from top to bottom.