2MeHCO3=Me2CO3+CO2+H2O
n(CO2)=1,12:22,4=0,05; n(MeHCO3)=0,05*2=0,1; M(MeHCO3)=8,4:0,1=84;
M(MeHCO3)= M(Me)+1+12+48;
M(Me)+61=84
M(Me)=23;
ответ:натрий.
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