Which group refers to organic molecules composed only of carbon and hydrogen?

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Multiple Choice

Which group refers to organic molecules composed only of carbon and hydrogen?

The main concept is that hydrocarbons are organic molecules built only from carbon and hydrogen. This makes them the simplest and most fundamental set of organic compounds, including saturated types like alkanes, unsaturated types like alkenes and alkynes, and even aromatic rings—all without any other elements. If a molecule contains oxygen, nitrogen, or other atoms, it isn’t a hydrocarbon, because it goes beyond just C and H. The other options describe broader or different groups: nucleic acids include sugars, phosphate, and nitrogenous bases; carbohydrates contain carbon, hydrogen, and oxygen in specific ratios; and organic compounds is a broad category that includes molecules with many other elements. So hydrocarbons are the term that precisely refers to molecules composed only of carbon and hydrogen.

The main concept is that hydrocarbons are organic molecules built only from carbon and hydrogen. This makes them the simplest and most fundamental set of organic compounds, including saturated types like alkanes, unsaturated types like alkenes and alkynes, and even aromatic rings—all without any other elements. If a molecule contains oxygen, nitrogen, or other atoms, it isn’t a hydrocarbon, because it goes beyond just C and H. The other options describe broader or different groups: nucleic acids include sugars, phosphate, and nitrogenous bases; carbohydrates contain carbon, hydrogen, and oxygen in specific ratios; and organic compounds is a broad category that includes molecules with many other elements. So hydrocarbons are the term that precisely refers to molecules composed only of carbon and hydrogen.

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