Matter is anything that has mass and takes up space. Matter is all around us. Matter exists in one of four phases, or states. The four states of matter are solid, liquid, gas, and plasma.

Interactive exercise. Assistance may be required. Click on each image below to learn more about each state of matter.

All matter can be classified as either a pure substance or a mixture. There are two types of pure substances, elements and compounds.

Interactive exercise. Assistance may be required. Click on each image to see a brief explanation.

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