https://www.khanacademy.org/science/cambridge-o-level-chemistry-cie/x8bc8fb44369617ed:acids-bases-and-salts/x8bc8fb44369617ed:preparation-of-salts/v/water-of-crystallisation-copper-sulphate 2026-04-29T07:20:45.495372596Z Water of crystallisation Copper sulphate Water of crystallisationCopper sulphate Khan Academy Pakistan video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Water of crystallisation Copper sulphate Water of crystallisationCopper sulphate https://cdn.kastatic.org/ka-youtube-converted/NXm0MvhyZ_Q.mp4/NXm0MvhyZ_Q.mp4 270 Preparation of salts https://www.khanacademy.org/science/cambridge-o-level-chemistry-cie/x8bc8fb44369617ed:acids-bases-and-salts/x8bc8fb44369617ed:preparation-of-salts/v/double-displacement-reaction 2026-04-29T07:20:45.495372596Z Double Displacement reaction Double Displacement reaction Khan Academy Pakistan video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Double Displacement reaction Double Displacement reaction https://cdn.kastatic.org/ka-youtube-converted/dCU8Z-cXq3o.mp4/dCU8Z-cXq3o.mp4 723 Preparation of salts https://www.khanacademy.org/science/hs-chemistry/x2613d8165d88df5e:solutions-acids-and-bases/x2613d8165d88df5e:solubility/v/double-replacement-reactions 2024-08-16T15:18:47.217883837Z Double replacement reactions Double replacement reactions occur when two compounds exchange ions, forming two new compounds. The driving force in these reactions is often the formation of a precipitate, a gas, or water. A solubility chart is commonly used to predict whether a potential product will be insoluble and therefore precipitate out of solution. This allows us to determine if the reaction will actually occur. Mahesh Shenoy video https://cdn.kastatic.org/ka_thumbnails_cache/0918daf4-a77a-4427-a43c-53bae09bbd3f_1280_720_base.png Double replacement reactions Double replacement reactions occur when two compounds exchange ions, forming two new compounds. The driving force in these reactions is often the formation of a precipitate, a gas, or water. A solubility chart is commonly used to predict whether a potential product will be insoluble and therefore precipitate out of solution. This allows us to determine if the reaction will actually occur. https://cdn.kastatic.org/ka-youtube-converted/KDGDLsUN8TQ.mp4/KDGDLsUN8TQ.mp4 732 Preparation of salts https://www.khanacademy.org/science/hs-chemistry/x2613d8165d88df5e:solutions-acids-and-bases/x2613d8165d88df5e:solubility/a/double-replacement-reactions 2026-04-29T07:20:45.495372596Z Learn and try: Double replacement reactions Definition and examples of double replacement reactions. Predicting and balancing neutralization and precipitation reactions.  article https://www.khanacademy.org/science/hs-chemistry/x2613d8165d88df5e:solutions-acids-and-bases/x2613d8165d88df5e:solubility/e/apply-double-replacement-reactions 2026-04-29T07:20:45.495372596Z Apply: Double replacement reactions Check your understanding of double replacement and precipitation reactions in this set of free, standards-aligned practice questions. Allen Ruch exercise https://www.khanacademy.org/science/hs-chemistry/x2613d8165d88df5e:solutions-acids-and-bases/x2613d8165d88df5e:solubility/e/apply-solubility-rules 2026-04-29T07:20:45.495372596Z Apply: Solubility rules Apply your understanding of solubility rules in this set of free, standards-aligned practice questions. Allen Ruch exercise https://www.khanacademy.org/science/cambridge-o-level-chemistry-cie/x8bc8fb44369617ed:acids-bases-and-salts/x8bc8fb44369617ed:preparation-of-salts/e/water-of-crystallization 2026-04-09T13:00:40.290711197Z Water of crystallization Let's practice writing the number of water of crystallization present in one unit of a given salt. exercise https://www.khanacademy.org/science/cambridge-o-level-chemistry-cie/x8bc8fb44369617ed:acids-bases-and-salts/x8bc8fb44369617ed:preparation-of-salts/e/uses-of-common-salts 2026-03-28T12:05:05.381528741Z Identify chemicals based on their uses Let's practice identifying some of the common salts based on their applications. exercise