Chemistry - 9202 OxfordAQA

The Properties Of Acids And Bases

Resumen

Swallow an indigestion tablet and something quietly dramatic happens in your stomach. A powder that would do nothing at all in a glass of water goes to work on a liquid strong enough to strip paint, and within a few minutes the burning stops. That rescue is the same event that farmers buy by the lorry load to repair sour fields, that power stations engineer into their chimneys to keep sulfur out of the sky, and that a technician performs a hundred times a week at a laboratory bench with a burette. One reaction, four completely different settings.

This lesson gets underneath it. You will find out what a base actually is and why only some bases earn the name alkali, why every acid you meet owes its behaviour to one particular ion, how a strip of paper dipped in a mixture of dyes can report the acidity of a solution in a colour you can read across a room, and why the salt that appears at the end of a neutralisation has one half of its name donated by the acid and the other half by the base. By the end you will be able to look at any acid and any base in the specification and name the product before you mix them.

Objetivos

  1. Metal oxides and hydroxides are bases. Soluble hydroxides are called alkalis.
  2. Acids react with bases to form salts. These reactions are called neutralisation reactions.
  3. The particular salt produced in any reaction between an acid and a base or alkali depends on: the acid used (hydrochloric acid produces chlorides, nitric acid produces nitrates, sulfuric acid produces sulfates); the metal in the base or alkali.
  4. Ammonia dissolves in water to produce an alkaline solution. It is used to produce ammonium salts.
  5. A solution of calcium hydroxide in water (limewater) reacts with carbon dioxide to produce calcium carbonate.
  6. Hydrogen ions, H+ (aq), make solutions acidic and hydroxide ions, OH- (aq), make solutions alkaline. The pH scale is a measure of the acidity or alkalinity of a solution. Students should be familiar with the pH scale from 0 to 14, and know that pH 7 is a neutral solution. Students should be able to describe the use of universal indicator to measure the approximate pH of a solution.
  7. In neutralisation reactions, hydrogen ions react with hydroxide ions to produce water. This reaction can be represented by the equation: H+ (aq) + OH- (aq) → H2O (l)

Mapa mental

Este tema esta esquematizado para ver como se conectan las ideas.

Abre el mapa mental en la app

Nota de la lección

The lining of your stomach secretes hydrochloric acid at a strength that would ruin most of the fabrics in your wardrobe. Usually a layer of mucus keeps that acid where it belongs. When the arrangement fails you feel it, and the remedy sold in every pharmacy is a small quantity of a metal compound: magnesium hydroxide, calcium carbonate, aluminium hydroxide, or some blend of them. None of these substances is medicine in any ordinary sense. They do not deaden a nerve or block a signal. They simply react with the acid and destroy it, and the relief you feel is the pH of your stomach contents climbing back towards a value your throat can tolerate.

Apunte completo disponible en la aplicacion Green Bridge

Instala la aplicacion Green Bridge CBT en tu movil u ordenador para acceder a toda la biblioteca IGCSE: examenes anteriores, criterios de correccion, mapas mentales, tarjetas de estudio y lecciones en audio.

Notas de lección completas con diagramas
Asistente de aprendizaje con IA
Simulacros cronometrados que se corrigen en cuanto terminas
Disponible en Android, Windows, macOS y Linux App para iOS proximamente

Evaluación de la lección

Felicitaciones por completar la lección del The Properties Of Acids And Bases. Ahora que has explorado el conceptos e ideas clave, es hora de poner a prueba tus conocimientos. Esta sección ofrece una variedad de prácticas Preguntas diseñadas para reforzar su comprensión y ayudarle a evaluar su comprensión del material.

Te encontrarás con una variedad de tipos de preguntas, incluyendo preguntas de opción múltiple, preguntas de respuesta corta y preguntas de ensayo. Cada pregunta está cuidadosamente diseñada para evaluar diferentes aspectos de tu conocimiento y habilidades de pensamiento crítico.

Utiliza esta sección de evaluación como una oportunidad para reforzar tu comprensión del tema e identificar cualquier área en la que puedas necesitar un estudio adicional. No te desanimes por los desafíos que encuentres; en su lugar, míralos como oportunidades para el crecimiento y la mejora.

  1. Which of these substances is an alkali? A. copper(II) oxide B. calcium carbonate C. potassium hydroxide D. sulfuric acid Answer: C
  2. Which salt is produced when magnesium oxide reacts with nitric acid? A. magnesium chloride B. magnesium nitrate C. magnesium sulfate D. magnesium nitride Answer: B
  3. Which statement about a solution of pH 12 is correct? A. It contains no hydroxide ions. B. It contains more hydroxide ions than hydrogen ions. C. It turns universal indicator red. D. It is neutral. Answer: B
  4. Which equation represents the neutralisation of an acid by an alkali? A. H+ (aq) + OH- (aq) -> H2O (l) B. H2 (g) + O2 (g) -> H2O (l) C. Na+ (aq) + Cl- (aq) -> NaCl (s) D. CaCO3 (s) -> CaO (s) + CO2 (g) Answer: A
  5. Carbon dioxide is bubbled through limewater. What is observed? A. The colourless solution turns cloudy white. B. The solution turns blue. C. A gas is given off that relights a glowing splint. D. A yellow precipitate forms. Answer: A

Resuelve estas preguntas en la aplicacion

Resuelve estas preguntas en la aplicacion

Practica preguntas simuladas

¿Quieres practicar preguntas simuladas sobre The Properties Of Acids And Bases? Descarga la aplicación Green Bridge CBT para acceder a preguntas simuladas y evaluaciones completas sobre este tema.

Descarga la aplicación en Google Playstore.

Todo lo que necesitas para destacar en JAMB, WAEC y NECO.

Green Bridge CBT Mobile App
Asistente de Chat de Aprendizaje Personalizado con IA
Más de 200.000 preguntas de examen de IGCSE, JAMB, WAEC y NECO.
Más de 1200 notas de lecciones
Soporte sin conexión: Aprende en cualquier momento y lugar.
Horario del Puente Verde
Resúmenes de Literatura y Preguntas Potenciales
Controla tu rendimiento y progreso.
Explicaciones detalladas para un aprendizaje integral