Answer the following :
(i) What is hydrolith ?
(ii) Which element of alkaline earth metals family do not give characteristic flame colouration ?
(iii) Which out NaOH or `Mg(OH)_2` is stronger base ?
(iv) Which element in the group 2 is radioactive ?
(v) Which out of `Mg^(2+), Ba^(2+), Ca^(2+)` has maximum ionic mobility in water ?

Explanation

(i) `CaH_2` (ii) Be , Mg (iii) NaOH (iv) Radium
(v) `Ba^(2+)` .