Which statement about atoms and molecules is correct?

• A. All molecules are made up of only one type of atom.
• B. A molecule consists of two or more atoms chemically bonded together.
• C. Atoms are always larger than molecules.
• D. Atoms can be broken down into molecules by physical means.

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the definitions of atoms and molecules. An atom is the smallest unit of an element that retains the chemical properties of that element, while a molecule is formed when two or more atoms chemically bond together.
2. Step 2: Analyze the first statement: 'All molecules are made up of only one type of atom.' This is incorrect because molecules can be made of different types of atoms (e.g., H2O has hydrogen and oxygen atoms).
3. Step 3: Analyze the second statement: 'A molecule consists of two or more atoms chemically bonded together.' This is correct because molecules are defined by the chemical bonding of atoms.
4. Step 4: Analyze the third statement: 'Atoms are always larger than molecules.' This is incorrect because molecules are made up of atoms, so molecules are generally larger than individual atoms.
5. Step 5: Analyze the fourth statement: 'Atoms can be broken down into molecules by physical means.' This is incorrect because atoms are fundamental units and cannot be broken down into molecules; molecules are made from atoms, not the other way around.