https://www.khanacademy.org/science/grade-11-chemistry-snc-aligned/x203b0fc81a964b2d:acid-base-chemistry/x203b0fc81a964b2d:strength-of-acids-and-bases/v/strong-and-weak-acids-bases-pk 2025-12-18T16:50:45.096818701Z Strong and weak acids/bases Created by Khan Academy video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Strong and weak acids/bases Created by Khan Academy https://cdn.kastatic.org/ka-youtube-converted/tZ7stSmlx0w.mp4/tZ7stSmlx0w.mp4 316 Strength of acids and bases https://www.khanacademy.org/science/chemistry/acids-and-bases-topic/copy-of-acid-base-equilibria/v/ka-and-acid-strength 2021-01-04T18:35:18Z Ka and acid strength How to write an equilibrium expression for an acid-base reaction and how to evaluate the strength of an acid using Ka video https://cdn.kastatic.org/googleusercontent/0w5OdvzBpJEgiioYkA2Ba_FaVaeLW-5dw4XjmK4oUU2bLvwwRA4dXF3nWZ3JLQPYh-qyCo1D1joNMldmkugmonlE Ka and acid strength How to write an equilibrium expression for an acid-base reaction and how to evaluate the strength of an acid using Ka https://cdn.kastatic.org/ka-youtube-converted/BeHOvYchtBg.mp4/BeHOvYchtBg.mp4 558 Strength of acids and bases https://www.khanacademy.org/science/chemistry/acids-and-bases-topic/copy-of-acid-base-equilibria/v/relationship-between-ka-and-kb 2021-07-29T03:21:16.460036972Z Relationship between Ka and Kb The relationship between Ka and Kb, and pKa and pKb. Examples of finding Ka of a weak acid given Kb of the conjugate base. video https://cdn.kastatic.org/googleusercontent/MQViSQw1ZiG-TBw0c9F7jyIyP97M9iP-gLWJYCcAUVnxkaVkHUBeOVOlsh5mWOkKzLFpglebZFYffPryb-ASLMw Relationship between Ka and Kb The relationship between Ka and Kb, and pKa and pKb. Examples of finding Ka of a weak acid given Kb of the conjugate base. https://cdn.kastatic.org/ka-youtube-converted/DGMs81-Rp1o.mp4/DGMs81-Rp1o.mp4 680 Strength of acids and bases https://www.khanacademy.org/science/grade-11-chemistry-snc-aligned/x203b0fc81a964b2d:acid-base-chemistry/x203b0fc81a964b2d:strength-of-acids-and-bases/a/relationship-between-ka-and-kb 2021-04-29T07:58:15Z Relationship between Ka and Kb Relationship between Ka of a weak acid and Kb for its conjugate base. Equations for converting between Ka and Kb, and converting between pKa and pKb.  article https://www.khanacademy.org/science/biology/water-acids-and-bases/acids-bases-and-ph/v/introduction-to-definition-of-ph 2021-03-18T10:33:22Z Definition of pH Introduction to pH and the pH scale. Examples of calculating pH of pure water, bleach, and orange juice.  video https://cdn.kastatic.org/googleusercontent/pf3RWNnKKyhvaMuHbtZSJKxlpJ9Iu0IfztzqlxyrLsXQ9_hjpmB8pUKkBShKg5y0rT0PZbPLO5ACXmIEbOtkTJs Definition of pH Introduction to pH and the pH scale. Examples of calculating pH of pure water, bleach, and orange juice.  https://cdn.kastatic.org/ka-youtube-converted/J7-GewgqWUQ.mp4/J7-GewgqWUQ.mp4 697 Strength of acids and bases https://www.khanacademy.org/science/hs-chemistry/x2613d8165d88df5e:solutions-acids-and-bases/x2613d8165d88df5e:intro-to-acids-and-bases/v/introduction-to-ph 2024-03-19T21:01:49.527176433Z Introduction to pH The pH scale is used to determine the acidity or basicity (alkalinity) of a substance. Acidic substances have pH values below 7, while basic substances have pH values above 7; neutral substances have a pH of 7. The pH scale is logarithmic, so each step represents a 10-fold change in concentration. Sal Khan video https://cdn.kastatic.org/googleusercontent/gH1DSPb-1zyfV6R9fjXld5DWVrmXbb1QVDaBRbvhapDJeuGGoBMuUBLYLYVUr1moO0mQnXTiJqy4oZGuifwVeio Introduction to pH The pH scale is used to determine the acidity or basicity (alkalinity) of a substance. Acidic substances have pH values below 7, while basic substances have pH values above 7; neutral substances have a pH of 7. The pH scale is logarithmic, so each step represents a 10-fold change in concentration. https://cdn.kastatic.org/ka-youtube-converted/oda2K4IFBaE.mp4/oda2K4IFBaE.mp4 322 Strength of acids and bases https://www.khanacademy.org/science/grade-11-chemistry-snc-aligned/x203b0fc81a964b2d:acid-base-chemistry/x203b0fc81a964b2d:strength-of-acids-and-bases/a/ph-poh-and-the-ph-scale 2021-04-29T07:59:30Z pH, pOH, and the pH scale Definitions of pH, pOH, and the pH scale. Calculating the pH of a strong acid or base solution. The relationship between acid strength and the pH of a solution.  article https://www.khanacademy.org/science/grade-11-chemistry-snc-aligned/x203b0fc81a964b2d:acid-base-chemistry/x203b0fc81a964b2d:strength-of-acids-and-bases/e/acids--bases--and-ph 2026-04-07T22:59:30.107127435Z Acids, bases, and pH Test your knowledge on acids, bases, and pH Ashley exercise https://www.khanacademy.org/science/ap-chemistry-beta/x2eef969c74e0d802:acids-and-bases/x2eef969c74e0d802:ph-and-poh-of-strong-acids-and-bases/v/strong-acid-solutions 2022-09-05T08:18:59.810508578Z Strong acid solutions Strong acids (such as HCl, HBr, HI, HNO₃, HClO₄, and H₂SO₄) ionize completely in water to produce hydronium ions. The concentration of H₃O⁺ in a strong acid solution is therefore equal to the initial concentration of the acid. For example, a solution of 0.1 M HNO₃ contains 0.1 M H₃O⁺ and has a pH of 1.0. Jay video https://cdn.kastatic.org/ka_thumbnails_cache/c266a6ef-efe2-45bb-88f7-bf92da5bab76_1280_720_base.png Strong acid solutions Strong acids (such as HCl, HBr, HI, HNO₃, HClO₄, and H₂SO₄) ionize completely in water to produce hydronium ions. The concentration of H₃O⁺ in a strong acid solution is therefore equal to the initial concentration of the acid. For example, a solution of 0.1 M HNO₃ contains 0.1 M H₃O⁺ and has a pH of 1.0. https://cdn.kastatic.org/ka-youtube-converted/pZ43GbTechI.mp4/pZ43GbTechI.mp4 378 Strength of acids and bases https://www.khanacademy.org/science/ap-chemistry-beta/x2eef969c74e0d802:acids-and-bases/x2eef969c74e0d802:ph-and-poh-of-strong-acids-and-bases/v/strong-base-solutions 2022-09-05T08:18:59.810508578Z Strong base solutions Strong bases (such as Group 1 and 2 metal hydroxides) dissociate completely in water to produce hydroxide ions. The concentration of OH⁻ in a strong base solution can therefore be determined from the initial concentration of the base and the stoichiometry of the dissolution. For example, the strong base Ba(OH)₂ dissociates to give two OH⁻ ions per formula unit, so a 0.1 M Ba(OH)₂ solution has an OH⁻ concentration of 0.2 M. Jay video https://cdn.kastatic.org/ka_thumbnails_cache/f7ff042c-9085-4e42-a9b3-f1f8a5c76307_1280_720_base.png Strong base solutions Strong bases (such as Group 1 and 2 metal hydroxides) dissociate completely in water to produce hydroxide ions. The concentration of OH⁻ in a strong base solution can therefore be determined from the initial concentration of the base and the stoichiometry of the dissolution. For example, the strong base Ba(OH)₂ dissociates to give two OH⁻ ions per formula unit, so a 0.1 M Ba(OH)₂ solution has an OH⁻ concentration of 0.2 M. https://cdn.kastatic.org/ka-youtube-converted/ffAiM67QomI.mp4/ffAiM67QomI.mp4 327 Strength of acids and bases https://www.khanacademy.org/science/ap-chemistry-beta/x2eef969c74e0d802:acids-and-bases/x2eef969c74e0d802:introduction-to-acids-and-bases/v/autoionization-of-water-ap 2022-10-05T02:43:18.611402953Z Autoionization of water In the autoionization of water, a proton is transferred from one water molecule to another to produce a hydronium ion (H₃O⁺) and a hydroxide ion (OH⁻). The equilibrium expression for this reaction is Kw = [H₃O⁺][OH⁻], where Kw is the autoionization constant for water. At 25°C, the value of Kw is 1.0 x 10⁻¹⁴. In pure water, the concentrations of H₃O⁺ and OH⁻ are equal, and the water is considered to be neutral. Jay video https://cdn.kastatic.org/ka_thumbnails_cache/d0ba3dbe-de0e-46b1-9180-ab648309ca22_1280_720_base.png Autoionization of water In the autoionization of water, a proton is transferred from one water molecule to another to produce a hydronium ion (H₃O⁺) and a hydroxide ion (OH⁻). The equilibrium expression for this reaction is Kw = [H₃O⁺][OH⁻], where Kw is the autoionization constant for water. At 25°C, the value of Kw is 1.0 x 10⁻¹⁴. In pure water, the concentrations of H₃O⁺ and OH⁻ are equal, and the water is considered to be neutral. https://cdn.kastatic.org/ka-youtube-converted/vt6WjF1O_08.mp4/vt6WjF1O_08.mp4 541 Strength of acids and bases https://www.khanacademy.org/science/grade-11-chemistry-snc-aligned/x203b0fc81a964b2d:acid-base-chemistry/x203b0fc81a964b2d:strength-of-acids-and-bases/a/water-autoionization-and-kw 2021-04-29T07:54:28Z Water autoionization and Kw Autoionization of water, the autoionization constant Kw, and the relationship between [H⁺] and [OH⁻] in aqueous solutions.  article https://www.khanacademy.org/science/ap-chemistry-beta/x2eef969c74e0d802:acids-and-bases/x2eef969c74e0d802:introduction-to-acids-and-bases/e/introduction-to-acids-and-bases 2025-05-23T18:26:12.433798667Z Introduction to acids and bases Check your understanding of pH, pOH, and Kw in this set of free practice questions designed for AP Chemistry students. exercise