Justify that the following reactions are redox reactions :
`2K(s)+F_(2)(g)to2K^(+)F^(-)(s)`

Explanation

`overset(0)(2K(s)) + overset(0)(F_(2)(g)) rarr overset(+1-1)(2K^(+) F^(-)(s))`
In this reaction, the oxidation state of K is increasing from 0 (in K) to +1 (in KEF) hence, K is undergoing oxidation. While the oxidation number of fluorine is decreasing from 0 (in `F_(2)`) to -1 (in KF) hence `F_(2)` is undergoing reduction. Therefore, it is a redox reaction.