Question

The decreasing order of boiling points of alkyl halides is

• A. RI > RBr > RCl > RF
• B. RF > RCl > RBr > RI
• C. RBr > RCl > RI > RF
• D. RCl > RF > RI > RBr

Answer 1

The correct option is A RI > RBr > RCl > RF

Intermolecular forces of attractions increases as​ molecular size increases.​ So, large amount​ of heat require to break strong intermolecular forces​ and thus boiling point increases.
Here, the order of molecular size is as follows : $RI>RBr>RCl>RF$ and thus boiling point also increases in same order.
$RI>RBr>RCl>RF$