Grade 9 - Atomic Structure, Periodic Table

Test yourself on Grade 9 - Atomic Structure, Periodic Table

• An imaginary element, Y, has two different isotopes.
  ²⁵Y has a percentage abundance of 25% and ²⁹Y has a percentage abundance of 75%.
  
  Which of the following is the relative atomic mass of Y?

• Sodium contains 11 electrons. What is the electronic structure of sodium?

• Calcium carbonate reacts with hydrochloric acid to form calcium chloride, carbon dioxide, and water. Which of the following is a balanced equation for this reaction?