A researcher collected the data shown to see how the concentration of thiosulfate in water affects the reaction time with hydrochloric acid. Which conclusion can the researcher draw?

A
As concentration increases, reaction time decreases.

B
There is no obvious mathematical relationship.

C
As concentration decreases, reaction time decreases.

D
As concentration increases, reaction time increases.

it is a good conductor

explanation:

it is the most commonly accepted one

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.