Question

it is the ______of an element which decides the group and the periodic of an element in which it is to be placed​

Answer 1

Answer:

Explanation:

The number of valence electrons in the atom determines the group number of that atom i.e. if an element has 4 valence electrons then it must belong to group IV A. Since sodium has 3 shells, it belongs to period 3. ... Hence, Sodium is present in group IA of period 3 in the modern periodic table

Answer 2

Answer:

no. of protons

Explanation:

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