Help with Chemistry
Hey Basil, I need some help with Chemistry again. This time it's about Moles.
1) Hydrogen and nitrogen react to form ammonia according to the reaction, 3 H2 + N2 --> 2 NH3. If 4.0 moles of H2 with 2.0 mol of N2 are reacted, how do many moles of NH3 will be produced in this reaction?
2) Hydrogen and nitrogen react to form ammonia according to the reaction, 3 H2 + N2 --> 2 NH3. If 4.0 moles of H2 with 2.0 mol of N2 are reacted, how many moles of what reactant are left over?
3) Using the formula below: ___ H2 + ___ O2 --> ___ H2O
If you start with 4 moles of H2 and 4 moles of O2, which is the limiting reactant?
For question 3, i balanced it with the coefficients 2 1 2
I then divided the 4 moles of H2 by the coefficient 2, and got 2. I divided 4 moles of O2 by the coefficient of 1, and got 4. I thought that the answer was H2, but the answer is O2. Can someone explain why?
5 Comments • Newest first
3. oxygen is limiting reagent, but hydrogen is left over. your teacher is wrong if they say hydrogen is limiting reagent.
1. 8/3 moles. If its 4 moles of H2 and 2 moles of N2, H2 is the limiting reagent because the ratio is 3:1 so you'd need 6 moles of H2 for 2 moles of N2. With 4 moles of H2, you get 8/3 moles of NH3 because the ratio is 3:2
2. If 4 moles of H2 react with 2moles of N2, N2 is the limiting reagent, so there will be 2/3 moles of N2 left because only 4/3 moles of N2 is used due to the 3:1 ratio so 2-(4/3)=2/3
3. First you find the coefficients so it's 2H2+O2->2H2O so if it's 4 and 4, O2 is the limiting reagent.
I know how to do this. I'm a biochemistry major but sadly I'm to lazy to type an explanation for each D: Srry
but why? can you explain?
I know it's hydrogen, but my teacher says it's oxygen. Is there some mistake?