Addition reaction

I need help on this question please. I've done 22a and b.i but I'm stuck on ii and iii.

ii) I wrote that the carbocation is more stable on carbon 3 than on carbon 2 so will form in greater amounts (the product on the right in the 2nd picture attached).
The mark scheme mentions that it's a tertiary halogenoalkane which I don't understand.

iii) I'm unsure how to start this question.
The mark scheme says compound D's formula is C7H16O but I thought it was C7H10O.

for bii) not too sure about your syllabus but have you learned on Markovnikoff's Rule? According to this rule, the hydrogen in HCL will go to the carbon which is bonded to the most number of hydrogen atoms. (Carbon-2)
Hence, the chlorine will go to carbon-3 forming a tertiary halogenoalkane i think.

I've learnt that rule, thank you. I thought before 3 alkyl groups meant it was tertiary.
So do you mean because the chlorine is on the 3rd carbon it forms a tertiary halogenoalkane?

Ah alright. Oh and nope. To know if something is a tertiary halogenoalkane you need to see where the halogen (chlorine) is bonded to. In this case the chlorine is bonded to carbon-3 which is bonded to, as you mentioned, three alkyl groups (hence tertiary). And not because its on the third carbon (sorry for the confusion).

If it was bonded to carbon-2, it wouldve been a secondary halogenoalkane as the carbon it is bonded to has a hydrogen group and only two alkyl ones.

That makes sense now. Could you give me an idea about the second question please?

Im sure its C7H10O.
7(12) + 10(1) + 16(1) = 110

Either way the Mr should be 110. Maybe its a typo that they put C7H16O instead?