2HCl+CaCO3=<span>CO2</span>+H2O+CaCl2
1)Mr(CaCO3)=40+12+3*16=100
M(CaCO3)=100
m(CaCO3)=1*100=100
2)Vm=22,4
3)x-m(чистого веществаCaCO3)
<span> X </span> = <span>V(CO2)</span> = > x= <span>100*4,48</span> = 20
m(CaCO3) Vm 22,4
4)m(мрамора)=25, а m(CaCO3)=20
ώ(массовая доля)= (m(CaCO3)/m(мрамора))*100% = (20/25)*100%=<span>80%</span>