Which of the following statements are correct?

a. Among halogens, the radius ratio between iodine and fluorine is maximum.

b. Leaving F — F bond, all halogens have weaker X — X bond than X — X' bond in interhalogens.

c. Among interhalogen compounds a maximum number of atoms are present in iodine fluoride.

d. Interhalogen compounds are more reactive than halogen compounds.

1. (a, b, c)
2. (b, c, d)
3. (a, c, d)
4. (a, b, d)


 



Hint: Down the group size of atom increases.

(a) Among halogens, radius ratio between iodine and fluorine is maximum because iodine has a maximum radius and fluorine has minimum radius. Hence statement one is correct. 
(b) It can be correctly stated as in general interhalogen compounds are more reactive than halogen. This is because X — X' bond in interhalogen is weaker than X — X bond in halogens except F — F bond. 

Hence, statement second is incorrect because halogens have a weaker X — X bond than X — X' bond in interhalogens
(c) Among interhalogen compounds the maximum number of atoms are present in iodine fluoride because the radius ratio of iodine and fluorine has the maximum value. Hence the third statement is correct.
(d) Interhalogen compounds are more reactive than halogens due to weaker X — X' bond as compared to X — X  of halogen compounds. Hence, statement fourth is correct.