Neutralisation

• What is the purpose of indicators in chemistry?

  Indicators are used to determine whether a solution is acidic or alkaline.
• What do acids produce when they react with metals, bases, and carbonates?

  Acids react with metals, bases, and carbonates to produce salts.
• What is neutralisation in chemistry?

  Neutralisation is the reaction between an acid and a base.
• What are the characteristics of a base?

  • A substance that reacts with an acid to neutralise it
  • Produces hydroxide ions when dissolved in water
  • Can form salts and water when reacting with acids
• What defines an acid in terms of ion production?

  An acid produces more hydrogen ions than hydroxide ions when dissolved in water.
• What is a salt in the context of acid-base reactions?

  A salt is the substance formed when the hydrogen ion in an acid is replaced by a metal ion.
• What are the characteristics of soluble bases?

  Soluble bases are called alkalis and can dissolve in water.
• What is the definition of an alkali?

  An alkali is a substance that produces more hydroxide ions than hydrogen ions when dissolved in water.
• What happens when a substance dissolves in water?

  When a substance dissolves, it breaks up and mixes completely with a solvent to produce a solution.
• What is the pH of alkaline solutions?

  Alkaline solutions have a pH greater than 7.
• What is the definition of an insoluble substance?

  An insoluble substance is unable to dissolve in a particular solvent.
• Why is sodium hydroxide classified as both a base and an alkali?

  Sodium hydroxide is a base because it reacts with acids and an alkali because it dissolves in water.
• What is the reaction of zinc oxide with hydrochloric acid?

  Zinc oxide reacts with hydrochloric acid to form zinc chloride and water.
• Is zinc oxide a base, an alkali, or both, and why?

  Zinc oxide is a base because it reacts with an acid to form a salt and water, but it is not an alkali because it does not dissolve in water.
• What occurs during a neutralisation reaction?

  • A reaction between an acid and a base
  • Produces a salt and water
  • Involves hydrogen ions from the acid and hydroxide ions from the alkali
• What is the pH of pure water?

  The pH of pure water is 7.
• How can the change in pH during a neutralisation reaction be measured?

  The change in pH can be measured using a pH probe and meter or estimated using a universal indicator solution and a pH colour chart.
• What is the key fact about acid-alkali neutralisation?

  • It is the reaction between hydrogen ions and hydroxide ions
  • It forms water as a product