Structural formula for ethene?

Structural formula for ethene?

• A. CH2 CH2
• B. CH3-CH3
• C. CH2=CH2
• D. CH2-CH3

Answer: (A)

Ethene is an alkene, so the key is a carbon–carbon double bond. In its simplest structural formula, each carbon is bonded to two hydrogens and shares a double bond with the other carbon, giving CH2=CH2. The double bond shows the two pairs of electrons being shared between the carbons, which is what defines an alkene and makes the molecule C2H4 overall. The option with CH2=CH2 accurately shows both the correct number of hydrogens and the essential C=C bond, matching ethene’s structure. The other options correspond to other hydrocarbons or unclear bonding: CH3-CH3 would be ethane with a single bond; CH2-CH3 would represent an ethyl fragment with a single bond; CH2 CH2 (without a bond symbol) doesn’t clearly show the necessary double bond. So the correct structural formula is CH2=CH2.

Ethene is an alkene, so the key is a carbon–carbon double bond. In its simplest structural formula, each carbon is bonded to two hydrogens and shares a double bond with the other carbon, giving CH2=CH2. The double bond shows the two pairs of electrons being shared between the carbons, which is what defines an alkene and makes the molecule C2H4 overall.

The option with CH2=CH2 accurately shows both the correct number of hydrogens and the essential C=C bond, matching ethene’s structure. The other options correspond to other hydrocarbons or unclear bonding: CH3-CH3 would be ethane with a single bond; CH2-CH3 would represent an ethyl fragment with a single bond; CH2 CH2 (without a bond symbol) doesn’t clearly show the necessary double bond. So the correct structural formula is CH2=CH2.