Answer:
To solve this problem the first thing you need to know is the equation for the reaction of hydrogen and nitrogen to give ammonia:
3 H2 + N2 → 2 NH3
So, for every mole of nitrogen, three moles of hydrogen are required and will result in the formation of 2 moles of ammonia.
Next, how many moles of hydrogen do we have. The molecular weight of hydrogen is 2 g/mol. So, 10 g of hydrogen is equal to 10 g/2g/mol = 5 moles of hydrogen.
OK, so the ratio of hydrogen/nitrogen is 3/2 and 5 moles of H2 will give 5*2/3 moles of ammonia or 10/3 or 3.33 moles of ammonia.
Now, there are two options. First, you an use the ideal gas law to calculate the Volume:
V = nRT/P = 3.33 * 0.082 * 273 / 1 = 74.54 L
The other way, which is based on the ideal gas law but…OK, so 1 mole of a gas at STP occupies 22.4 L. Therefore
V = 3.33 mol * 22.4 L/mol = 74.6 L
OK, a little round off error but pretty close. 74.54 L s a better answer.
