Reactions of Acids

• What is the general equation for the reaction of a metal with an acid?

  The general equation for the reaction between a metal and acid is:

  metal + acid ⟶ salt + hydrogen
• Which metals will react with dilute acids?

  Metals above hydrogen in the reactivity series will react with dilute acids.
• True or False?

  Effervescence is produced when an acid reacts with a metal.

  True.

  Effervescence is produced when an acid reacts with a metal , due to the formation of hydrogen gas.
• Why are metals such as sodium and potassium not commonly reacted with acids?

  Metals such as sodium and potassium are not commonly reacted with acids because the reactions are dangerous / violent / explosive.
• Name the salt formed when zinc reacts with sulfuric acid.

  The salt formed when zinc reacts with sulfuric acid is zinc sulfate.
• Write the word equation for the reaction of magnesium with hydrochloric acid.

  The word equation for the reaction of magnesium with hydrochloric acid is:

  magnesium + hydrochloric acid ⟶ magnesium chloride + hydrogen
• Which metal and acid are required to form iron sulfate?

  The metal and acid required to form iron sulfate are:

  • Iron,
  • Sulfuric acid.
• In metal-acid reactions, which species is oxidised?

  In metal-acid reactions, the metal atoms are oxidised.
• In metal-acid reactions, which species is reduced?


  In metal-acid reactions, the hydrogen ions are reduced.
• True or False?

  In metal-acid reactions, the metal gains electrons.

  False.

  In metal-acid reactions, the metal loses electrons.
• Write the half equation for the oxidation of zinc by hydrochloric acid.

  The half equation for the oxidation of zinc by hydrochloric acid:

  Zn → Zn2+ + 2e-
• True or False?

  Redox reactions involve the transfer of electrons.

  True.

  Redox reactions involve the transfer of electrons. Reduction involves gaining electrons, while oxidation involves losing electrons.
• Why are metal-acid reactions considered redox reactions?


  Metal-acid reactions are considered redox reactions because both oxidation and reduction occur simultaneously.
• Which species is oxidised in the following reaction?

  Mg + 2H+⟶ Mg2+ + H2

  Magnesium is oxidised in the following reaction, because it has lost electrons.

  Mg + 2H+⟶ Mg2+ + H2
• Which species is reduced in the following reaction?

  Fe + 2H+⟶ Fe2+ + H2

  Hydrogen ions are reduced in the following reaction, because they gain electrons.

  Mg + 2H+⟶ Mg2+ + H2
• What is a base?

  A base is a chemical that neutralises acids.
• What are the products of a neutralisation reaction between an acid and a base?

  The products of a neutralisation reaction between an acid and a base are salt and water.
• True or False?

  All bases are soluble in water.

  False.

  Many bases are insoluble in water.
• What is an alkali?

  An alkali is a base that is soluble in water, forming an alkaline solution.
• What three product are formed when an acid reacts with a metal carbonate?

  The three products formed when an acid reacts with a metal carbonate are:

  • Salt,
  • Water,
  • Carbon dioxide.
• What determines the identity of the salt produced in a neutralisation reaction?

  The identity of the salt produced depends on:

  • The acid used,
  • The positive ions in the base.
• True or False?

  Hydrochloric acid produces sulfate salts.

  False.

  Hydrochloric acid produces chloride salts.
• What type of salt does sulfuric acid produce?

  Sulfuric acid produces sulfate salts.
• What type of salt does nitric acid produce?

  Nitric acid produces nitrate salts.
• Write the symbol equation for the reaction of hydrochloric acid and copper(II) oxide.

  The symbol equation for the reaction of hydrochloric acid and copper(II) oxide is:

  2HCl + CuO → CuCl2 + H2O
• Write the word equation for nitric acid reacting with magnesium oxide.

  The word equation for nitric acid reacting with magnesium oxide is:

  nitric acid + magnesium oxide → magnesium nitrate + water
• True or False?

  The balanced symbol equation for the reaction of sulfuric acid and potassium carbonate is:

  2HCl + K2CO3 ⟶ 2KCl + H2O

  False.

  The balanced symbol equation for the reaction of sulfuric acid and potassium carbonate is:

  2HCl + K2CO3 ⟶ 2KCl + H2O + CO2
• How is a soluble salt made?

  A soluble salt can be made by the reaction of an acid with a solid insoluble substance, such as :

  • metal.
  • metal oxide.
  • metal hydroxide.
  • metal carbonate.
• Why is the insoluble base added in excess during the preparation of a soluble salt?

  The insoluble base is added in excess to ensure that all of the acid has reacted.
• What step is taken to remove the excess insoluble base after the reaction?

  The excess insoluble base is removed by filtration.
• What is left in the solution after the excess base is removed?

  After removing the excess base, only the salt and water remain in the solution.
• Write the balanced symbol equation for the preparation of copper(II) sulfate from copper(II) oxide.

  The balanced symbol equation is:

  CuO (s) + H2SO4 (aq) ⟶ CuSO4 (s) + H2O (l)
• Define the term insoluble base.

  An insoluble base is a base that does not dissolve in water.
• How are crystals produced from a salt solution?

  The solution is heated gently and then left to cool.
• What does pH measure?

  pH measures the concentration of hydrogen ions (H+) in a solution.
• What is the pH range for acids?

  Acids have pH values below 7.
• What is the pH range for alkalis?

  Alkalis have pH values above 7.
• What pH value is considered neutral?

  A pH value of 7 is considered neutral.
• True or False?

  A lower pH indicates a more acidic solution.

  True.

  A lower pH indicates a more acidic solution.
• What is universal indicator?

  Universal indicator is a wide range indicator made of a mixture of different plant indicators which operate across a broad pH range.