I assume you mean this reaction.
N2 + 3H2 --> 2NH3
0.90 moles N2 (3 moles H2/1 mole N2)
= 2.7 moles hydrogen gas needed
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How many moles of C are needed to react with 0.490 mole SO2?
6moles of hydrogen
Ca + 2 H2O ------> Ca(OH)2 + H2 so 2 moles of calcium react with 4 moles of water.
1.28moles
The answer is 1,25 moles iron(III) oxide.
10 moles of nitrogen dioxide are needed to react with 5,0 moles of water.
How many moles of C are needed to react with 0.490 mole SO2?
The answer is 699 moles perchloric acid.
6moles of hydrogen
Ca + 2 H2O ------> Ca(OH)2 + H2 so 2 moles of calcium react with 4 moles of water.
These reagents doesn't react.
0.083
1.28moles
1.35
63 g of water are needed.
4NH3 + 3O2 -----> 2N2 + 6H2O 4 moles of ammonia react with 3 of oxygen. So 10 moles of ammonia requires 7.5 moles of oxygen.
The answer is 1,25 moles iron(III) oxide.