Question

Tungsten(VI) oxide can be reduced to tungsten by heating it with carbo, as shown in the reaction:

2WO3(s) + 3C(s) <---> 2W(s) + 3CO2(g)

If the original mass of WO3 is 37.0 g, how many grams of CO2 must be collected from the reaction in order to infer that the solid that remains is pure tungsten? (Round to the nearest whole number)

Answer 1

I'm not quite understanding if I should take the molar mass of WO3 and CO2 and subtract them or if I should get the number of moles for each and find the mass that way.

Answer 2

I don't think you have the right picture.
Do it this way.
mols WO3 = grams/molar mass = ?
Use the coefficients in the balanced equation to convert mols WO3 to mols CO2.
Now convert mols CO2 to grams CO2. g CO2 = mols CO2 x molar mass CO2. This gives you the grams of CO2 needed to obtain a 100% conversion of WO3 to W, then round to the nearest whole number.