https://www.khanacademy.org/science/grade-7-science-tx/xe25057200abc6bd6:changes-in-matter-and-solutions 2026-07-03T03:00:41.306580382Z Changes in matter and solutions Build on knowledge of elements, compounds, and mixtures to investigate the difference between physical and chemical changes. Dig deeper into homogeneous mixtures, also known as solutions, to understand their importance across many fields. unit