list any two distinguishing feature between mendeleev periodic table and the modern periodic table
Answers
Answer:
The major difference is that the elements in Mendeleev's periodic table were arranged by atomic mass and the modern periodic table arranges elements by atomic number.
Explanation:
Mendeleev's periodic table
Modern periodic table
Mendeleev's periodic table is based on atomic mass. Elements are arranged in increasing order of atomic mass.
Modern periodic table is based on atomic number.
Elements are arranged in increasing order of atomic mass.
There are a total of 7 groups and 6 periods. There are a total of 18 groups and 7 periods.Elements having similar properties were placed directly one another. Elements having same valence shell were placed in the same period while elements having the same number of valence electons were placed in the same period.