选B.
根据沉淀得出CO2的质量是4.4g
Ca(OH)2+CO2=CaCO3↓+H2O
44 100
x　　10g
44/x=100/10
x=4.4g
H2O的质量是6.2-4.4=1.8g
C的质量是4.4*(12/44)=1.2g
C、H质量和是1.2+0.2=1.4g,所以还含有1.6g的O元素
H的质量是1.8*(2/18)=0.2g
C的物质的量是n=m/M=1.2/12=0.1mol
H的物质的量是n=m/M=0.2/1=0.2mol
O的物质的量是n=m/M=1.6/16=0.1mol
C、H、O的个数比是1:2:1,最简式是CH2O.
A.葡萄糖是C6H12O6,蔗糖是C12H22O11,蔗糖不满足.
B.醋酸是C2H4O2,果糖是C6H12O6,满足.
C.乙醇是C2H6O,葡萄糖是C6H12O6,乙醇不满足.
D.乙醛是C2H4O,葡萄糖是C6H12O6,乙醛不满足.