Making soluble salts

• What can soluble salts be made from?

  Acid and alkali reactions
• Why can't you tell when the acid is neutralised in a reaction with alkali?

  There is no signal indicating completion
• What should you avoid when adding alkali to acid in salt preparation?

  Adding excess alkali to the acid
• What is the consequence of adding excess alkali to the acid?

  The salt would be contaminated with alkali
• What is the procedure for titration to find the right amount of alkali?

  1. Measure acid into a conical flask
  2. Add indicator drops
  3. Slowly add alkali from a burette
  4. Stop when the indicator changes color
  5. Use the same volumes without indicator for the reaction
• What does the solution contain after the reaction is complete?

  Only the salt and water
• What should you do after the reaction to obtain the salt?

  Evaporate off some water and crystallise
• What type of indicator should be used for titrations?

  One with a single, clear color change
• Why is universal indicator not suitable for titrations?

  Its color change is too gradual
• How can soluble salts be made using an insoluble base?

  1. React an acid with an insoluble base
  2. Heat the acid in a water bath
  3. Add the base to the acid
  4. Filter off excess solid
  5. Evaporate water to crystallise the salt
• What is produced when copper oxide reacts with sulfuric acid?

  Copper sulfate and water
• What happens to the solution after evaporating some water from the copper sulfate solution?

  It crystallises to form blue crystals
• What color are the crystals formed from copper sulfate?

  Blue
• What are the steps to make soluble salts using an acid and an insoluble base?

  1. Heat the acid in a water bath
  2. Add the insoluble base to the acid
  3. Ensure excess solid sinks to the bottom
  4. Filter off excess solid
  5. Evaporate water and crystallise the salt