required practical: making salts

• Salts contain a positive ion and a negative ion
• Positive ion in salts comes from the metal ion
• Metal ion can come from the metal itself, metal oxide, metal hydroxide, or metal carbonate
• Negative ion in salts comes from the acid
• Negative ion in copper sulfate is the sulfate ion (SO4^2-)
• Steps to make pure crystals of a soluble salt like copper sulfate
• Start with a fixed amount of dilute sulfuric acid as the limiting reactant
• Gently heat the acid until almost boiling, but do not let it boil
• Add small amounts of copper oxide to the acid using a spatula
• Stir the solution with a glass rod until it turns blue (color of copper sulfate)
• Continue adding copper oxide until the solution is clear blue, stop if some powder remains after stirring
• Filter the solution to remove any unreacted copper oxide using a filter funnel and filter paper
• Heat the copper sulfate solution in an evaporating basin over boiling water until around half the solution remains
• Leave the solution for 24 hours in a cool place for copper sulfate crystals to form
• Scrape the copper sulfate crystals onto paper towel and gently pat and dry to obtain pure dry crystals