Question

The Modern periodic table has 18 vertical columns known as groups and Seven

Horizontal rows are known as periods. Valency of an element is determined by

the number of electron present in the outer most shell of its atom. Size of an atom

can also be determined from the modern periodic table.

i) Which of the following forms the basis of the modern periodic

table?

a) Atomic Mass

b) Atomic Number

c) Number of Nucleons

d) None of these
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Answer 1

Answer:

Atomic number

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