In the case of alkali metals, the covalent character decreases in the order.

Options

A. `MF gt MCl gt MB rgt MI`
B. `MFgt MCl gt MI gt MBr`
C. `MI gt MBr gt MCl gt MF`
D. `MCl gt MI gt MBr gt MF`

Answer

C

Explanation

For a given metal ion `(M^(+))`, the degree of polarization of the negative ion by the positive ion is decided by the polarizability of the negative ion which increases with its size (for a given charge). The greater the polarization, the higher the covalent character is:
Size of negative ion `(I^(-)gtBr^(-)gtCl^(-)gtF)`
Covalent character `(MIgtMBrgtMClgtMF)`