What volume of "NH"_3 at STP is produced if 25.0 "g" of "N"_2 is reacted with an excess of "H"_2 in the reaction "N"_2 + 3"H"_2 -> 2"NH"_3?

1 Answer
Mar 16, 2016

40.0"L"

Explanation:

1 "mol" of "N"_2 has mass of 28.0 "g"

Therefore, 25.0"g" of "N"_2 in moles is

frac{25.0"g"}{28.0 "g/mol"} = 0.893 "mol"

Each molecule of "N"_2 will produce 2 molecules of "NH"_3.

Therefore, the 2 times the amount of "NH"_3 will be produced.

2 xx 0.893 "mol" = 1.79 "mol"

One mole of an ideal gas has a volume of 22.4"L" at STP.

Therefore, the volume occupied by 1.79 "mol" of "NH"_3 is

1.79 "mol" xx 22.4 "L/mol" = 40.0 "L"

That's it. But bear in mind that you need to somehow remove the excess "H"_2 before the container will have a volume of 40.0 "L".