A 3.0 mole sample of KBrOz was decomposed according to the following
equation. How many moles of O2 are formed? *
2KBrO3 → 2KBr + 302

Explanation:

2KBrO₃ => 2KBr + 3O₂

3.0 mol KBrO₃        =>     3/2 x (3 mole O₂) = 4.5 mole O₂*

*Ratio of moles must produce a larger number of moles for Oxy than KBrO₃.

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.