Chemistry Regents Practice Test 2026 – The All-in-One Guide to Exam Success!

The three states of matter are solid, liquid, and gas. In a solid, particles are closely packed together, resulting in a definite shape and volume. In a liquid, particles are still close but can move past one another, allowing liquids to take the shape of their container while maintaining a definite volume. In the gas state, particles are far apart and move freely, leading to no definite shape or volume, as gases expand to fill their container.

This understanding of the states of matter is foundational in chemistry and helps explain a variety of physical properties and behaviors of substances. Other choices may include terms that describe specific conditions or states, but they do not represent the basic, widely accepted categories that encompass all forms of matter. For example, 'plasma' is another state of matter but is not one of the three primary states. 'Vapor' refers to the gaseous state of a substance that is normally a liquid or solid at room temperature, and 'energy' is not a state of matter but a property that can affect matter.