Which statement is true about alkanes and alkenes in terms of saturation?

Which statement is true about alkanes and alkenes in terms of saturation?

• A. Alkanes are saturated, alkenes are unsaturated
• B. Alkanes are unsaturated, alkenes are saturated
• C. Both are unsaturated
• D. Both are saturated

Answer: (A)

Saturation describes whether a hydrocarbon has as many hydrogens as possible for its carbon skeleton. When all carbon–carbon bonds are single, the molecule is saturated because it can hold the maximum number of hydrogens. If there’s a carbon–carbon double bond, the molecule has fewer hydrogens than the saturated form, making it unsaturated. Alkanes have only single bonds between carbon atoms, so they are saturated. Alkenes contain at least one carbon–carbon double bond, which reduces the hydrogen count, making them unsaturated. For example, alkanes follow the formula CnH2n+2, while alkenes have CnH2n, reflecting that hydrogen deficit caused by the double bond. So the true statement is that alkanes are saturated and alkenes are unsaturated.

Saturation describes whether a hydrocarbon has as many hydrogens as possible for its carbon skeleton. When all carbon–carbon bonds are single, the molecule is saturated because it can hold the maximum number of hydrogens. If there’s a carbon–carbon double bond, the molecule has fewer hydrogens than the saturated form, making it unsaturated.

Alkanes have only single bonds between carbon atoms, so they are saturated. Alkenes contain at least one carbon–carbon double bond, which reduces the hydrogen count, making them unsaturated. For example, alkanes follow the formula CnH2n+2, while alkenes have CnH2n, reflecting that hydrogen deficit caused by the double bond.

So the true statement is that alkanes are saturated and alkenes are unsaturated.