Question

if the mass no of an element is 14 and its atomic number is 17 then what would be its valency ?​

Answer 1

Answer:

For a neutral atom,

Atomic number = Number of protons = Number of electrons

Electronic configuration for an atom with 17 electrons in it is (2,8,7)

Valence electrons are the electrons present in the outermost shell of an atom.

∴

The number of valence electrons = 7

Valency of an atom with more than 4 valence electrons = 8 - Number of valence electrons

∴

Valency = 8 - 7 = 1