Friday, 27 September 2013

CBSE Class 10th Science | Chapter 5. Periodic Classification of Elements | Solved Exercises

Things to remember :
  • From only 30 elements known around year 1800, today we have list of 114 known elements
  • Elements are classified on the basis of similarities in their properties.
  • Döbereiner grouped the elements into triads and Newlands gave the Law of Octaves.
  • MendelĂ©ev arranged the elements in increasing order of their atomic masses and according to their chemical properties.