The type of hybridisation and number of lone pair (s) of electrons of Xe in XeOF₄, respectively, are:

The effect of lanthanoid contraction in the lanthanoid series of elements by and large means :

The decreasing order of ease of alkaline hydrolysis for the following esters in

Consider the following reduction processes :
Zn²⁺ + 2e^– $$ \to $$ Zn(s) ; E^o = – 0.76 V
Ca²⁺ + 2e^– $$ \to $$ Ca(s); E^o = –2.87 V
Mg²⁺ + 2e^– $$ \to $$ Mg(s) ; E^o = – 2.36 V
Ni² + 2e^– $$ \to $$ Ni(s) ; E^o = – 0.25
The reducing power of the metals increases in the order :