How many moles of H2O are used to make 3.12 moles of NH3

4.73 mol NH

Explanation:

What we're doing here is calculating basic mole-mole relationships, something that you'll be doing quite a bit!

The steps to solving mole-mole problems like this are

write the balanced chemical equation for the reaction (this is given)

divide the number of moles of the given known substance (3.55) by that substance's coefficient in the chemical equation (3)

multiply that number by the coefficient of the substance you're trying to find (4)

Using simple dimensional analysis, it looks like this:

4.68 H2O is needed to make 3.12 moles of NH3

Explanation:

Using stoichiometry, we can convert Moles of NH3 into Moles of H20

since we're converting moles to moles, we take the given mole of NH3

3.12, and multiply it by the Mole ratio, which in this case is (H20/NH3) or (6/4)

so then: 3.12 * 6/4 = 4.68 mols of H2O

6.4 cm (max) - 25 cm (min)