Which of the following is always involved in a scientific inquiry?
a.
knowing the correct answer before you start
b.
guessing what would happen instead of doing experiments
c.
coming up with questions based on observation and reasoning
d.
conducting surveys to ask people's opinions on various subjects

plasma is the state of matter where the substance is ionized and has no definite shape or volume. the fact of being ionized makes the substance a good electrical conductor.

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.