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In this activity, students will use their knowledge of the periodic table and periodic trends to add fictional elements to a periodic table based on their properties. Once the elements are in the correct place they will reveal a hidden message. This review activity will help students prepare for a summative assessment such as a unit test or final exam.

  • Um is in the 3rd period and has three electrons in its highest p-orbitals.
  • St is a gas that does not belong to a specific family.
  • Ea, Nd and Dy are all alkali metals. 
  • F, En, and K are alkaline earth metals. 
  • A and Rb are halogens. 
  • Ma, U and R are all elements that have a full octet. 
  • Me and Ex both form -2 ions. 
  • The ionization energy trend for the elements that form +1 ions is Ea < Nd < Dy.
  • The electronegativity value for En is greater than K, but it is less than F.
  • A has a smaller atomic radius than Rb.
  • R is the noble gas with the largest atomic radius.
  • Me has a smaller value for ionization energy than Ex.
  • Th, Or and E are all located in the second period. 
  • Ma has one less proton than Nd.
  • Jo would form a +3 cation and is a metal.
  • The electronegativity values of Th is less than E but greater than Or.
  • Ys can only form a +4 ion.


Write the hidden message in the space below.