sodium oxide reacts with carbon dioxide to form sodium carbonate. How much carbon dioxide is needed to produce 79g or sodium carbonate?

2 answers

first you must find the # of moles of NaCO3 produced:
79g NaCO3/83g(per mole of NaCO3)NaCO3 = .95 moles NaCO3

then you compare the # of moles in the equation, its a 1:1 molar ratio
NaO + CO2 ==> NaCO3
(use dimensional analysis)

.95 mol NaCO3| 1 mol NaO | 39g NaO
____________________________________
| 1 mol NaCO3 | 1 mol NaO

you multiply across the top and divide the by the bottom. get rid of the units that repeat on the top and bottom and you're left with grams of NaO
37g NaO needed.
Na2O + CO2 ==> Na2CO3
The molar mass of Na2CO3 is 106.