Among BCl3, BF3, BBr3 , which one has maximum bond angle and why?
Boron halides show sp2 hybridisation but due to electronegativity difference between halides, the bond angle will show variations in these.
Remember: Bond angle of any molecule is inversely proportional to the electronegativity of surrounding atoms i.e., Lessar the electronegativity of attached atoms then more is the bond angle.
the order of electronegativity of halides is F> Cl > Br
so, the correct order of bond angle will be BBr3 > BCl3> BF3