CH3CHO\mathrm{CH}_{3} \mathrm{CHO}CH3CHO
HCHO\mathrm{HCHO}HCHO
CH3CH2CHO\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CHO}CH3CH2CHO
CCI3CHO\mathrm{CCI}_{3} \mathrm{CHO}CCI3CHO
b , d