# Calculate the number of molecules of CO2 and the number of grams H2O produced when 0.450 mole of O2 reacts. .?

Calculate the number of molecules of CO2 and the number of grams H2O produced when 0.450 mole of O2 reacts with sufficient C3H7OH. Please show the steps in getting to the answers. Thanks!

The equation is:

2C3H7OH + 9O2 >>>> 6CO2 + 8H2O

Also, I'm looking for the number of molecules of CO2 AND the number of grams H2O

How did you get the numbers x = 0.4 moles of H2O and x = 0.3 moles of CO2?

### 1 Answer

- 9 years agoBest Answer
So firstly, you need an equation.

2C3H7OH + 9O2 ---> 6CO2 + 8H2O

Then you form a proportion to find the number of moles of H2O produced from 0.450 moles of O2

9moles of O2 = 8moles of H2O

----------------------- -----------------------

0.450moles of O2 x

x = 0.4 moles of H2O

Then you get the grams of H2O by dividing by the GFM (Grand Formula Mass)

0.4moles / 1.00g/mole = 0.4 grams of H2O

To get the molecules of CO2, you do almost the same thing.

9moles of O2 = 6moles of CO2

------------------------- ----------------------

0.450 moles of O2 x

x = 0.3 moles of CO2

Then you multiple by Avogadro's number to get the # of molecules.

0.3moles (6.02 x 10^23 molecules/moles) = 1.806 x 10^23 molecules

Source(s): AP Chemistry