What is the structural formula for ethanol?

What is the structural formula for ethanol?

• A. CH3 CH2 OH
• B. CH3OH
• C. C2H5OH
• D. CH3 CH2 O H

Answer: (A)

Structural formula shows how atoms are connected in a molecule. Ethanol has two carbon atoms in a chain with a hydroxyl group on the second carbon, so the connectivity should be CH3-CH2-OH. Writing this as CH3CH2OH shows exactly that: a CH3 group attached to a CH2 group, which is bound to an OH group. This is the conventional structural depiction of ethanol. The option CH3OH is methanol (one carbon). The formula C2H5OH gives only the molecular formula, not how the atoms are joined. The spaced CH3 CH2 O H conveys the same bonds but is less standard; the clearest representation is CH3CH2OH.

Structural formula shows how atoms are connected in a molecule. Ethanol has two carbon atoms in a chain with a hydroxyl group on the second carbon, so the connectivity should be CH3-CH2-OH. Writing this as CH3CH2OH shows exactly that: a CH3 group attached to a CH2 group, which is bound to an OH group. This is the conventional structural depiction of ethanol. The option CH3OH is methanol (one carbon). The formula C2H5OH gives only the molecular formula, not how the atoms are joined. The spaced CH3 CH2 O H conveys the same bonds but is less standard; the clearest representation is CH3CH2OH.