In the classification system of matter, how many domains are there?

• A. Two domains: pure substances and mixtures
• B. Four domains: solids, liquids, gases, and plasma
• C. Three domains: elements, compounds, and mixtures
• D. Five domains: atoms, molecules, ions, compounds, and mixtures

Answer: (A)

Verified step by step guidance

1. Understand that the classification of matter can be approached from different perspectives, such as physical states or composition.
2. Recognize that one common classification system divides matter into two main categories: pure substances and mixtures.
3. Identify that pure substances can further be divided into elements and compounds, which are chemically distinct forms of matter.
4. Acknowledge that mixtures can be homogeneous (solutions) or heterogeneous, based on the uniformity of their composition.
5. Consider that another classification system categorizes matter based on physical states: solids, liquids, gases, and plasma, which are determined by temperature and pressure conditions.