Boron- 11
Atomic #
Atomic mass
# of protons
# of neutrons
# of electrons

Atomic mass - 11

# of protons - 5

# of neutrons - 6

# of electrons- 5

substituting a hydrogen atom with a halogen in a hydrocarbon:

- the single bond remains single. a is wrong.

- the bond with hydrogen is as strong as with a halogen. c is wrong

- a hydrocarbon is saturated if there is no double bond. we do not know that so d is wrong.

- carbon will always have four valence electrons. e is wrong.

by elimination, the correct answer is b. the boiling point of the new compound increases.