A compound with molecular formula CH2O2 is

Step 1: Analyze the question We need to identify which class of organic compound has the molecular formula CH₂O₂.

Step 2: Concept Different homologous series have different general formulas and functional groups:

• Carboxylic acids: R-COOH, general formula CₙH₂ₙO₂
• Esters: R-COOR', general formula CₙH₂ₙO₂, but the smallest ester (methyl methanoate) has 2 carbons (C₂H₄O₂)
• Alkanols: CₙH₂ₙ₊₁OH, with only one oxygen atom
• Carbohydrates: Cₓ(H₂O)ᵧ, with many carbons (at least 3 in the simplest sugars)

Step 3: Solution With n = 1, CₙH₂ₙO₂ gives CH₂O₂.

Structure: H-COOH (methanoic acid, also called formic acid).

• Carbon: 1
• Hydrogen: 1 (on C) + 1 (on OH) = 2
• Oxygen: 2 (one C=O and one OH)

Checking the other options:

• A. Carbohydrate: This is not a carbohydrate, since carbohydrates need at least 3 carbons.
• C. Alkanol: An alkanol has only one oxygen, so it is ruled out.
• D. Ester: An ester needs at least two carbons (one in the acid part and one in the alkyl part), so the simplest ester is C₂H₄O₂. CH₂O₂ cannot be an ester.

Step 4: Answer CH₂O₂ is methanoic acid, a carboxylic acid.

Tip: Carboxylic acids and esters share the general formula CₙH₂ₙO₂, so they are isomers. To tell them apart, check the carbon count. With only 1 carbon, it must be the acid (HCOOH), since an ester needs at least 2 carbons.