How many moles are required to react with 4.5 moles of H2?

N2 + 3 H2 > 2 NH3

1.5 mol

Explanation:

Given data:

Number of moles of H₂ = 4.5 mol

Number of moles of N₂ = ?

Solution:

Chemical equation:

N₂ + 3H₂     →        2NH₃

Now we will compare the moles of hydrogen and nitrogen.

                  H₂         :        N₂

                    3         :          1

                  4.5        :          1/3×4.5 = 1.5 mol

Thus, 1.5 moles of nitrogen are required to react with hydrogen.  

c is the answer because when something is left after something evaporates that shows the chemical change.

assuming that your periodic table has eighteen columns, you should highlight   the four elements in the third column from the left of the table.

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