Final answer:
To calculate the moles of Na2O that can be made from 12.3 moles of Na, we use the stoichiometry of the reaction 4Na + O2 → 2Na2O, which shows that 6.15 moles of Na2O can be produced.
Step-by-step explanation:
The calculation of moles of Na2O formed from an amount of Na involves using the stoichiometry of the balanced chemical reaction 4Na + O2 → 2Na2O. For every 4 moles of Na, 2 moles of Na2O are produced. Therefore, if you start with 12.3 moles of Na, you can find the moles of Na2O by setting up a proportion:
By solving for x, you get:
x = (12.3 moles Na) × (2 moles Na2O) / (4 moles Na) = 6.15 moles Na2O
So, the answer is a) 6.15 moles of Na2O.