CaCO3+2HCl=CaCl2+H2O+CO2↑
2 1
n(HCl) 0.1mol
n(HCl)=0.2mol
盐酸溶质的质量m=nM=0.2*36.5=7.3g
溶质的质量分数=7.3/100*100%=7.3%
答：盐酸溶液中溶质的质量分数为7.3%