6.72 liters of carbon dioxide were passed through the sodium hydroxide solution.

6.72 liters of carbon dioxide were passed through the sodium hydroxide solution. Subtract the mass of the medium salt formed during the reaction.

Given:
V (CO2) = 6.72 l

To find:
m (salt) -?

1) CO2 + 2NaOH => Na2CO3 + H2O;
2) n (CO2) = V / Vm = 6.72 / 22.4 = 0.3 mol;
3) n (Na2CO3) = n (CO2) = 0.3 mol;
4) m (Na2CO3) = n * M = 0.3 * 106 = 31.8 g.

Answer: The mass of Na2CO3 is 31.8 g.