KA 5: Acids, Bases, Salts

• Why are acids and bases important in chemistry?

  They are essential in many chemical processes
• What are bases defined as?

  Water-soluble alkalis
• How are the terms alkali and base related?

  All bases are alkalis, not vice versa
• What can happen when pH levels are too low or too high?

  They can be dangerous
• What does the pH scale measure?

  Acidity and alkalinity
• What is the pH scale range?

  0 to 14
• What indicates a higher concentration of H+ ions?

  Lower pH values
• What indicates a higher concentration of OH- ions?

  Higher pH values
• What is the relationship between H+ and OH- ions in pure water?

  They are equal
• What happens to the pH when an acid is diluted?

  The pH rises towards 7
• What happens to the pH when an alkali is diluted?

  The pH falls towards 7
• What do soluble non-metal oxides produce when dissolved in water?

  Acidic solutions
• What do soluble metal oxides produce when dissolved in water?

  Alkaline solutions
• What is a neutralisation reaction?

  Reaction between an acid and a base
• What are the products of a neutralisation reaction?

  Salt and water
• What does a reaction between a metal oxide and an acid produce?

  Salt and water
• What does a reaction between a metal hydroxide and an acid produce?

  Salt and water
• What does a reaction between a metal carbonate and an acid produce?

  Salt, water, and carbon dioxide
• What type of salts are produced from hydrochloric acid?

  Chloride salts
• What type of salts are produced from sulphuric acid?

  Sulphate salts
• What type of salts are produced from nitric acid?

  Nitrate salts
• What are spectator ions?

  Ions that do not participate in reactions
• What is a net ionic equation?

  Equation after eliminating spectator ions
• What are titrations used for?

  Measuring solution volume for reactions
• What is a standard solution?

  Solution of accurately known concentration
• What is the purpose of an indicator in titrations?

  To show when the end point is reached
• When are titre volumes considered concordant?

  When measurements are within 2cm³
• What is the method for determining the concentration of an acid in titrations?

  1. Clean and set up equipment
  2. Measure known volume of acid into conical flask
  3. Add indicator to alkali standard solution
  4. Wash burette with standard solution
  5. Pour standard solution into burette
  6. Record volume from bottom of meniscus
  7. Open tap while swirling flask
  8. Measure volume when acid changes colour
  9. Repeat until concordant results are obtained
  10. Calculate concentration of acid
• What are common acids?

  Hydrochloric, nitric, and sulphuric acids
• What are common alkalis?

  Calcium hydroxide, sodium hydroxide, lithium hydroxide
• What happens to the pH of an acid when it is diluted?

  The pH rises towards 7
• What happens to the pH of an alkali when it is diluted?

  The pH falls towards 7
• What do soluble non-metal oxides produce when dissolved in water?

  Acidic solutions
• What do soluble metal oxides produce when dissolved in water?

  Alkaline solutions
• What is a neutralisation reaction?

  Reaction between an acid and a base
• What are the products of a neutralisation reaction?

  Salt and water
• What does a reaction between a metal oxide and an acid produce?

  Salt and water
• What does a reaction between a metal hydroxide and an acid produce?

  Salt and water
• What does a reaction between a metal carbonate and an acid produce?

  Salt, water, and carbon dioxide
• What type of salts are produced from hydrochloric acid?

  Chloride salts