Atomic Structure Test
1. The atomic number of Aluminium is 13 and the atomic number of Argon is 18. Complete the shell
diagrams below to show the electronic configuration of EACH atom.
(2 marks)
2. Naturally occurring element Y consists of 85 % 2311Y and 15 % 2511Y. Determine the
average mass number of naturally occurring element Y.
(2 marks)
3. Explain why the two isotopes of element Y have the same chemical properties.
(1 mark)
4. What is a radioactive isotope?
(1 mark)
5. List TWO uses of radioactive isotopes.
(2 marks)