1、NaHCO3----------------------------------CO2
84g/mol 4.48L/22.4L/mol=0.2mol
x g
x=84*0.2=16.8g
m(Na2CO3)=38-16.8 g=21.2g
m(NaHCO3)/m(Na2CO3)=16.8g/21.2g
2、2NaHCO3----2CO2-------------------O2
33.6g
n(O2)=33.6g/168g/mol*0.5=0.1mol
V(O2)=22.4L/mol*0.1mol=2.24L