making soluble salts

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

  1. Start with dilute sulfuric acid as the limiting reactant.
  2. Gently heat the acid until almost boiling.
  3. Add copper oxide to the acid and stir until the solution turns blue.
  4. Filter out unreacted copper oxide.
  5. Evaporate the solution to form crystals.
  6. Leave the solution for 24 hours to allow crystals to form.
  7. Scrape and dry the crystals.
• What is the appearance of copper oxide?

  It is a black powder
• Why is it important to ensure no acid remains at the end of the reaction?

  Because remaining acid would contaminate the salt
• What happens to the solution when copper oxide is added to the acid?

  The copper oxide reacts and the solution turns blue
• What should you do if the solution remains clear blue after adding copper oxide?

  Stop adding copper oxide
• What is the purpose of filtering the solution?

  To remove unreacted copper oxide
• How do you make crystals of copper sulfate from the solution?

  By evaporating the solution until half remains and then leaving it to cool
• How long should the solution be left to form crystals?

  24 hours
• What is the final product of the process described in the video?

  Pure dry crystals of copper sulfate
• What should you do after the crystals have formed?

  Scrape them onto a paper towel and gently pat them dry
• What equipment is used in the first stage of making a soluble salt?

  • Dilute sulfuric acid
  • Spatula
  • Glass rod
  • Filter funnel
  • Filter paper
  • Evaporating basin
• How does the process of making copper sulfate using a metal oxide compare to using a metal carbonate?

  The stages are similar, but the reactants differ
• What is the role of heating the dilute sulfuric acid?

  To ensure the acid is reactive without boiling over
• What color indicates the presence of copper sulfate in the solution?

  Blue
• Why is it important to gently heat the acid?

  To prevent it from boiling over and causing danger
• What happens to the solution after the copper oxide has reacted completely?

  The solution becomes neutral
• What is the purpose of using a glass rod during the reaction?

  To stir the solution
• What is the first step in making a soluble salt?

  Start with a fixed amount of dilute sulfuric acid
• What is the significance of the term "limiting reactant" in this context?

  It refers to the reactant that will run out first
• How does the filtration process contribute to the purity of the final product?

  It removes any unreacted insoluble substances
• What should be done if the solution is still clear after adding copper oxide?

  Stop adding copper oxide
• What is the final step in the process of making copper sulfate crystals?

  Gently patting the crystals dry
• What is the importance of leaving the solution in a cool place after evaporation?

  To allow the copper sulfate crystals to form
• What is the appearance of the final product after drying?

  Pure dry crystals of copper sulfate
• How does the process of making copper sulfate relate to the concept of solubility?

  It demonstrates how soluble salts are formed from reactions
• What are the potential hazards of boiling dilute sulfuric acid during the experiment?

  It could bubble over and cause danger
• What is the role of the evaporating basin in the crystallization process?

  To hold the solution while it is heated for evaporation
• What is the color of the solution when copper sulfate is formed?

  Blue
• Why is it necessary to gently heat the copper sulfate solution during evaporation?

  To prevent rapid boiling and loss of solution
• What should you do with the copper sulfate crystals after they are formed?

  Scrape them onto a paper towel and gently pat them dry
• What is the significance of the blue color in the solution?

  It indicates the presence of copper sulfate
• How does the reaction between copper oxide and sulfuric acid illustrate the concept of neutralization?

  It shows the reaction of an acid with a base to form a salt
• What is the purpose of stirring the solution during the reaction?

  To ensure even mixing and reaction of the copper oxide