JEE Main 2014 · 12 Apr · Shift 1 · Chemistry Q54

← JEE Main 2014 · 12 Apr · Shift 1

ChemistrySingle correct+4 / -1Question 54 of 90

In the presence of peroxide, HCl and HI do not give anti-Markownikoff's addition to alkenes because :

One of the steps is endothermic in HCl and HI

Both HCl and HI are strong acids

HCl is oxidizing and the HI is reducing

All the steps are exothermic in HCl and HI

Answer and worked solution

Official answer: A

In the radical chain, one propagation step is endothermic: H-Cl is too strong to give up H, and with HI the addition of $\ce{I^.}$ to the alkene is uphill. So only HBr shows the peroxide effect.

Topics:Alkenes Reactive intermediates

← Previous question Next question →

JEE Main 2014 · 12 Apr · Shift 1, Chemistry question 54