Limiting Reagents: Practice Problem 2: Starting from Grams

I have walked you through my thought process as I worked through the problem below. Each thought I had - I wrote it as a step. You need to show work in order to receive full credit!
You will need your periodic table for this problem:

An unbalanced chemical equation is given as: ___Na + ___O2 --> ___Na2O
If you have 100 g of sodium and 60 g of oxygen…

A. Find the number of grams of sodium oxide produced by each reactant.
1st Step - Balance the Equation
2nd Step - Convert mass of Na to moles of Na
3rd Step - Convert moles of Na to moles of Na2O (hint: see ratio between Na and Na2O in your balanced equation)
4th Step - Convert moles of Na2O to grams of Na2O
5th Step - Repeat Steps 2 - 4 by substituting Na with O2
6th Step - Determine the limiting reactant and the amount of sodium oxide it produces
7th Step - The amount that it produces is the grams of sodium oxide that will be produced in the reaction.


B. Find the mass of excess reactant left over at the conclusion of the reaction.
1st Step - State what the excess reactant is from the previous problem - no quantity needed. (hint: It is not the limiting reagent)
2nd Step - Determine what is being asked in the question.
The question is asking how much of the excess reactant is needed to produce the amount of sodium oxide determined by the limiting reactant.
3rd Step - Convert grams of product to grams of excess reactant
4th Step - Determine the difference between the amount given in the initial problem and the amount used. There should be excess left over - which is why it is the excess reactant.