Statement - I : Iodine is least basic whereas fluorine is most basic, among halogens
Statement - II : The reactivity of halogens increases from fluorine to iodine .

Statement I is incorrect. Among halogens, fluorine is the least basic while iodine is the most basic. Basicity refers to the ability of a substance to accept a proton (H⁺ ion) to form a conjugate acid. Fluorine has a very small atomic size, high electronegativity, and low polarizability, which makes it difficult to accept a proton, making it the least basic among halogens. Iodine has a larger atomic size, lower electronegativity, and higher polarizability, making it easier to accept a proton, making it the most basic among halogens.

Statement II is correct. The reactivity of halogens increases from fluorine to iodine. This is because the atomic size of halogens increases down the group, making the outermost electron farther from the nucleus, and hence, easier to lose. This makes the elements more reactive as we move down the group. As a result, the reactivity of halogens increases from fluorine to iodine.