What is the number of moles in 3.2x10^24 atoms of nitrogen? A. 1.9 moles
B. 5.3 moles
C.9.5 moles
D. 19.2 moles

Option B

Explanation:

Use Avogadro constant of 6.02 x 10^23

For Option A,

1.9 moles x (6.02 x 10^23) = 1.1438 x 10^24

For Option B,

5.3 moles x (6.02 x 10^23) = 3.1906 x 10^24

For Option C,

9.5 moles x (6.02 x 10^23) = 5.719 x 10^24

For Option D,

19.2 moles x (6.02 x 10^23) = 1.1558 x 10^25

Therefore, the nearest one to 3.2 x 10^24 is Option B

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.