How many grams of oxygen are produced if you have 10.0 grams of water available for the following reaction? 2H2)-> 2H2 + O2

How many grams of oxygen are produced if you have 10.0 grams of water available for the following reaction? 2H2)-> 2H2 + O2

1 Answer
Feb 15, 2018

8.90g.

Explanation:

This is our balanced equation (I think you meant to write 2H2O instead of 2H2)?):

2H2O2H2+O2

From this balanced equation, we know that for every 2 moles of water, there will be 1 mole of oxygen gas, or O2.

First, let's find the number of moles of H2O in 10.0g:

number of moles=mass of samplemass of 1 mole

We know the mass of the sample (10.0g), but we're still missing the mass of 1 mole of water—but, we can find that using the masses of 2 moles of hydrogen and 1 mole of oxygen!:

2×H+O=2×1.008+16.00=18.02g

Let's plug that into our equation:

number of moles=10.0g18.02g=0.555

For 2 moles of water, we get 1 mole of O2.
That means that, for 0.555 moles of water, we get 0.5552=0.278 moles of O2.

Now that we know the number of moles of O2, we can find its mass by multiplying the number of moles by the mass of 1 mole.
We can find the mass of 1 mole of O2 using the same method as we did for H2O:

2×O=2×16.00=32.00g
mass=0.278×32.00g=8.90g