https://www.khanacademy.org/science/grade-6-science-snc-aligned/x19bc096754f0b9af:mixtures/x19bc096754f0b9af:pure-substances-and-mixtures/v/classification-of-matter 2022-10-31T23:33:27.733635026Z Classification of matter Matter is anything has mass and that occupies space. Matter can be classified into two categories: pure substances and mixtures. Pure substances are further broken down into elements and compounds. Mixtures are physically combined substances that can be mixed heterogeneously or homogeneously. Sal Khan video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Classification of matter Matter is anything has mass and that occupies space. Matter can be classified into two categories: pure substances and mixtures. Pure substances are further broken down into elements and compounds. Mixtures are physically combined substances that can be mixed heterogeneously or homogeneously. https://cdn.kastatic.org/ka-youtube-converted/FNYDRzG7fuE.mp4/FNYDRzG7fuE.mp4 468 Matter and its three states https://www.khanacademy.org/science/class-9-chemistry/x46dd29ce84a663ea:matter-in-our-surroundings/x46dd29ce84a663ea:states-of-matter/v/states-of-matter-in 2025-08-06T20:09:57.016070308Z States of matter (Bonus video) How many states of matter exist? How do they differ? Let's find out! Vibhor Pandey video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw States of matter (Bonus video) How many states of matter exist? How do they differ? Let's find out! https://cdn.kastatic.org/ka-youtube-converted/QkiULYmCO3g.mp4/QkiULYmCO3g.mp4 735 Matter and its three states https://www.khanacademy.org/science/bridge-course-class-11th-chemistry/x426c9d2c554669cb:states-of-matter/x426c9d2c554669cb:properties-of-matter/e/the-states-of-matter 2026-04-21T09:50:34.424034119Z The states of matter. Let's solve a few problems to identify the different states of matter and their properties. Aanchal Arora exercise https://www.khanacademy.org/science/cambridge-o-level-physics-cie/x0e04e0cb682fb793:kinetic-particle-model-of-matter/x0e04e0cb682fb793:states-of-matter/e/solid-liquid-and-gas 2026-04-28T11:00:37.315336883Z Solid, liquid and gas Let's try to distinguish between a solid, liquid and gas Vibhor Pandey exercise https://www.khanacademy.org/science/hs-chemistry/x2613d8165d88df5e:states-of-matter/x2613d8165d88df5e:liquids-solids-and-gases/e/apply-properties-of-solids 2026-05-22T03:20:56.431702691Z Apply: Properties of solids Apply your understanding of intermolecular forces to predict macroscopic properties in solids in this set of free practice questions. Emily Cizmas exercise https://www.khanacademy.org/science/exam-preparation-class-6th/x196eb96f0f1caea0:week-3/x196eb96f0f1caea0:air/v/activity-air-occupies-space 2023-06-26T03:56:33.129173029Z Activity: Air occupies space Let's show that air occupies space with a simple activity! Vibhor Pandey video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Activity: Air occupies space Let's show that air occupies space with a simple activity! https://cdn.kastatic.org/ka-youtube-converted/Hc4kDe-Fptw.mp4/Hc4kDe-Fptw.mp4 55 Matter and its three states https://www.khanacademy.org/science/up-science-grade-6-revision-course-full-term/x017c12e57b64cfa8:week-4/x017c12e57b64cfa8:untitled-257/v/explanation-air-occupies-space 2023-06-26T03:56:33.129173029Z Explanation: Air occupies space Let's look at the explanation of the activity - Air occupies space! Vibhor Pandey video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Explanation: Air occupies space Let's look at the explanation of the activity - Air occupies space! https://cdn.kastatic.org/ka-youtube-converted/0tvaXRcuBow.mp4/0tvaXRcuBow.mp4 71 Matter and its three states https://www.khanacademy.org/science/up-science-grade-6-revision-course-full-term/x017c12e57b64cfa8:week-4/x017c12e57b64cfa8:untitled-257/v/explanation-air-is-present-around-us 2023-06-26T03:56:33.129173029Z Explanation: Air is present around us Let's look at the explanation of the activity - Air is present all around us! Vibhor Pandey video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Explanation: Air is present around us Let's look at the explanation of the activity - Air is present all around us! https://cdn.kastatic.org/ka-youtube-converted/yyoz7OV4Q0E.mp4/yyoz7OV4Q0E.mp4 77 Matter and its three states https://www.khanacademy.org/science/hs-chemistry/x2613d8165d88df5e:states-of-matter/x2613d8165d88df5e:gases/e/apply-properties-of-gases 2026-04-27T14:30:54.817409388Z Apply: Properties of gases Apply your understanding of intermolecular forces to predict macroscopic properties in gases in this set of free practice questions. Donna Fig exercise https://www.khanacademy.org/science/grade-6-science-snc-aligned/x19bc096754f0b9af:matter-as-particles/x19bc096754f0b9af:particle-theory-and-states-of-matter/e/differentiate-between-solids-liquids-and-gases 2026-04-07T22:23:57.656416987Z Differentiate between solids, liquids and gases. Classification of things around us on the basis of physical properties into solids, liquids and gases. Revathi exercise https://www.khanacademy.org/math/cc-third-grade-math/imp-measurement-and-data/imp-volume/v/liter-intuition 2021-06-30T20:49:32Z Understanding volume (liters) Sal talks about what volume means. He also examines the volume of real objects in liters. video https://cdn.kastatic.org/googleusercontent/9PMEUeQ1_WrqxMBe-azsvZqCCMifDOdB40z5u9nPqpUZvkRZUNw5Wn88_fZQndZQxLF6J6aNc5rk91w-V6iyHl7pyw Understanding volume (liters) Sal talks about what volume means. He also examines the volume of real objects in liters. https://cdn.kastatic.org/ka-youtube-converted/mLRYCaYVWFc.mp4/mLRYCaYVWFc.mp4 288 Matter and its three states https://www.khanacademy.org/math/cc-third-grade-math/imp-measurement-and-data/imp-volume/e/estimating-volume 2021-06-30T20:49:26Z Estimate volume (milliliters and liters) Practice estimating the volume of real life objects using milliliters and liters. Lindsay exercise https://www.khanacademy.org/math/cc-third-grade-math/imp-measurement-and-data/imp-volume/e/volume-word-problems-1 2026-04-07T22:59:30.107127435Z Word problems with volume Solve word problems involving volume.  Estimate the volume of items. Lindsay Spears exercise