Question

ammonia is commonly used in cleaning solutions, as well as in manufacturing and water purification. its chemical formula is nh₃. the model below represents ammonia. based on the model, which statement best describes ammonia? ○ a. ammonia is composed of atoms of one type that are joined together to form an extended structure. ○ b. ammonia is composed of molecules that are joined together to form an extended structure. ○ c. ammonia is composed of atoms of one type that can freely move past each other. ○ d. ammonia is composed of molecules that can freely move past each other.

Explanation:

1. Analyze Option A: Ammonia has formula \(NH_3\), so it has two types of atoms (N and H), not one. Eliminate A.
2. Analyze Option B: The model shows separate \(NH_3\) molecules (each blue - white group is a molecule), and ammonia is a molecular substance with molecules that are not in an extended structure (like a network solid). Eliminate B.
3. Analyze Option C: Ammonia has two types of atoms (N and H), not one. Also, in ammonia (a gas or liquid), it's molecules moving, not single - type atoms. Eliminate C.
4. Analyze Option D: Ammonia is a molecular compound (\(NH_3\) molecules). In the gaseous or liquid state (implied by the model showing separate molecules), the \(NH_3\) molecules can freely move past each other. This matches the properties of molecular substances.

Answer:

D. Ammonia is composed of molecules that can freely move past each other.