Which of the following answers best describes how velocity and acceleration are related
velocity is the rate of change in acceleration
acceleration is always negative, and velocity is always positive
acceleration is the rate of change of velocity
acceleration is another word for velocity

c is the answer because when something is left after something evaporates that shows the chemical change.

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.