Which of the following statements are true?

Question

3-Bromopentane reacts with OH- to give 2-pentene. Which of the following
statements are true?



a) 3-Bromopentane is a Lewis base in this reaction

b) Hydroxide ion is a Bronsted base in this reaction

c) The byproduct of this reaction is Br2

d) Br- anions are produced in this reaction

e) One mole of 3-bromopentane reacts with two moles of OH- in this reaction

f) This is an addition reaction

Answer 1

I think it's B only because i'm pretty sure none of the other ones are right.

Answer 2

The hydroxide pulls a H+ off of the 3-bromopentane, leaving the carbon atom next to the bromine with a lone pair and a negative charge. The lone pair attaches to the adjacent carbon, pushing the Br, and the pair of electrons holding it, off as Br-.

So...

A is false. OH- is the only base in the reaction--3-bromopentane is actually acting as a Lewis acid.

B is true. OH- is a base no matter what system you use,and in this case it's taking an H+ to neutralize itself, so it's definitely acting as a base.

C is false. Bromine is a byproduct, but as Br- ions, not Br2 molecules.

D is true. Br- anions are produced.

E is false. 3-bromopentane reacts in a 1-1 ratio with OH-.

F is false. This is an elimination reaction.

So only B and D are true.

Answer 3

b and d.