Explain why 1-iodopropane is hydrolysed faster than 1-bromopropane

explain why 1-iodopropane is hydrolysed faster than 1-bromopropane?

i think the guy above is trying to be too smart all you need to know is the bond round the carbon and iodine C-I has a lower bond enthalpy (enthalpy is the minimum energy to break bonds) than the bond round carbon and bromide atom C-B so its easier to break despite bromide having a higher electronegative (the ability to attract a pair of electrons) sp that's why its faster. and chemistry is wonderful :)

Hi Mystery Questioner

Both of these halogenoalkanes are hydrolysed by an SN2 mechanism -- ie Substitution Nucleophilic 2nd Order . It is 2nd order because they are Primary Halogenoalkanes.

In SN2 the halogen polarises the C-Hal bond so that the C becomes delta + and the Hal delta -.

This delta + carbon is attacked the Nucleophile [ in this case H2O] and, at the same time, the halogen leaves as I minus or Br minus. It's called ''Synchronous Make and Break '' For this to happen the C-hal bond must break. How easy it is to break depends on the C -Hal bond strength

C-I bond strength is about 230 kJ per mole and C -Br is about 290 kJ per mole

So C- I will break easier than C - Br ---- 1 iodopropane hydrolyses faster than 1 bromopropane

GOTIT ? GOOD Good Luck in Your Studies. Chemistry is wonderful, innit?