Which of the following statements about organic molecules is true?

• A. Organic molecules are always soluble in water.
• B. Organic molecules are always formed through ionic bonds.
• C. Organic molecules cannot contain nitrogen atoms.
• D. Organic molecules primarily consist of $C$ and $H$ atoms.

Answer: (D)

Verified step by step guidance

1. Begin by understanding the basic definition of organic molecules. Organic molecules are primarily composed of carbon atoms, often bonded with hydrogen, oxygen, nitrogen, and other elements.
2. Consider the solubility of organic molecules. While some organic molecules are soluble in water, many are not. Solubility depends on the presence of polar functional groups that can interact with water.
3. Examine the type of bonding in organic molecules. Organic molecules typically involve covalent bonding rather than ionic bonding. Covalent bonds involve the sharing of electrons between atoms.
4. Evaluate the presence of nitrogen in organic molecules. Nitrogen is a common element in organic chemistry, found in amino acids, nucleic acids, and other important biological molecules.
5. Identify the primary composition of organic molecules. The statement that organic molecules primarily consist of carbon and hydrogen atoms is true, as these are the foundational elements in organic chemistry.