posted by Erika on .
How many grams of calcium oxide, CaO, can be produced from 4.20 g of calcium metal and 1.60 g of oxygen gas?
Erika, please don't change names with each post.
This is a limiting reagent problem.
1. Write the equation and balance it.
2Ca + O2 ==> 2CaO
2. Convert 4.20 g Ca to mols. Convert 1.60 g O2 to mols remembering that mols = grams/molar mass.
3. Using the coefficients in the balanced equation, convert mols Ca from step 2 to mols CaO. Do the same and convert mols O2 to mols CaO. Both of these numbers can't be correct. The smaller number will be the correct one to use and that will be the limiting reagent.
4. Convert mols CaO from step 3 to grams CaO. Mols x molar mass = grams.
Post your work if you get stuck.