(a) Write ionic equations for the reaction of acidified potassium permanganate with following:
(i) Oxalic acid,
(ii) `H_(2)S`
(iii) Sulphite ion.
(b) Describe the reactivity of actinoids.

Explanation

(a) (i) `2MnO_(4)^(-)+ 16H^(+) +5C_(2)O_(4)^(2-) to 2Mn^(2+)+ 8H_(2)O+ 10CO_(2)`
(ii) `2MnO_(4)^(-)+ 16H^(+)+ 5S^(2-)to 2Mn^(2+)+ 8H_(2)O+5S`
(iii) `2MnO_(4)^(-)+ 6H^(+)+ 5SO_(3)^(2-) to 2Mn^(2+)+ 3H_(2)O+ 5SO_(4)^(2-)`
(b) Actinoids are highly reactive metals in the finely divided state due to low ionisation enthalpies.
eg. (i) They react with boiling water.
(ii) They combine with most of the non-metals at moderate temperatures.
(iii) They are attacked by hydrochloric acid.