Making soluble salts

• What is the main objective of the video on making a soluble salt?

  To describe how to make a soluble salt using an acid
• Why is making a soluble salt considered a required practical?

  Because it is likely to have a specific question on it in exams
• What is an example of a soluble salt mentioned in the video?

  Copper sulfate
• What is a key component of all salts?

  All salts contain a positive ion
• What is the positive ion in copper sulfate?

  The metal ion $Cu^{2+}$
• From where can the metal ion in a salt come?

  From the metal itself, metal oxide, metal hydroxide, or metal carbonate
• Why can't copper sulfate be made by reacting copper with dilute sulfuric acid?

  Because copper is not reactive enough for that reaction
• What are the four sources of metal ions mentioned?

  Metal itself, metal oxide, metal hydroxide, metal carbonate
• What is the negative ion in copper sulfate?

  The sulfate ion $SO_4^{2-}$
• What acid is used to make copper sulfate?

  Sulfuric acid
• What is the first step in making pure crystals of a soluble salt?

  Start with a fixed amount of dilute sulfuric acid
• Why is dilute sulfuric acid considered the limiting reactant?

  Because it will run out during the reaction
• What should be avoided when heating the dilute sulfuric acid?

  Allowing it to boil
• What happens when copper oxide is added to the heated dilute sulfuric acid?

  The copper oxide reacts and the solution turns blue
• When should you stop adding copper oxide to the solution?

  When the solution is clear blue and no powder remains
• What is done to remove unreacted copper oxide from the solution?

  Filter it away using a filter funnel and filter paper
• What is the purpose of evaporation in the process of making copper sulfate crystals?

  To concentrate the solution until crystals form
• How long should the solution be left to form copper sulfate crystals?

  24 hours
• What should be done to the copper sulfate crystals after they form?

  Scrape them on a paper towel and gently pat them dry
• What is the final product of the process described in the video?

  Pure dry crystals of copper sulfate
• What are the steps involved in making pure crystals of a soluble salt like copper sulfate?

  1. Start with a fixed amount of dilute sulfuric acid.
  2. Gently heat the acid without boiling.
  3. Add copper oxide and stir until the solution turns blue.
  4. Filter out unreacted copper oxide.
  5. Evaporate the solution until half remains.
  6. Leave the solution for 24 hours to form crystals.
  7. Scrape and dry the crystals.
• What are the characteristics of copper oxide used in the reaction?

  • It is a black powder.
  • It reacts with dilute sulfuric acid to form copper sulfate.
  • It is insoluble, allowing for easy filtration.
• What are the differences between using a metal oxide and a metal carbonate in making soluble salts?

  • Both can react with acids to form salts.
  • Metal oxides produce water and a salt.
  • Metal carbonates produce carbon dioxide, water, and a salt.