Question

Plz answer fast the question is in the photo
its due very soon
and no links

Answer 1

Explanation:

A) i) 19 protons

ii) 20 nueteons

iii) 1S2 2S2 2P6 3S2 3P6 4S1 or it can be written as 2,8,8,1

iv) 1

Answer 2

I) Number of Protons – 19

Because atomic number is 19

ii) Number of neutrons – 20

Mass number = No of protons + No of neutrons

39 = No of protons + 19

No of protons = 39 – 19 → 20

iii) Electronic configuration of the element X – 2,8,8,1

By using Octate rule where there can be 2 or 8 electrons in a shell.

iv) Number of valence electrons – 1

Because 1 is in the outermost shell so the no of electrons outermost shell has that is only the no. of valence electrons.

ii) In the picture