Question

4. 1) Why isotopes occupy the same position in periodic table?
II) An element is represented as 31X15. Name the valence shell and
mention the number of electrons present in valence shell. (1.5+1.5=3]

plz help it's urgent ​

Answer 1

Answer:

1 because isotopes have equal no. of protons and electron. so have similar chemical properties. thus they are placed on equal position

2 phosphorus.

Valence shell M

Valence shell has 5 electron