How many moles of sodium will react with water to produce 2.0 mol of hydrogen in the following reaction? 2Na(s) + 2H20(1) - 2NaOH(aq) + H2(g)

4.0 moles of sodium will react with water to produce 2.0 mol of hydrogen

Explanation:

The balanced chemical equation is:

According to stoichiometry :

1 mole of is produced by = 2 moles of

Thus 2.0 moles of are produced by =  of

Thus 4.0 moles of sodium will react with water to produce 2.0 mol of hydrogen

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.