Question

the element W X Y and Z have atomic number 9, 12 ,16 ,18 respectively. which element have noble gas

Answer 1

hère is your answer mate...

thé élément Z is à noble gas...that is ARGON

Answer 2

e.c of w:1s^22s^22p^5

here in the outermostshell there are only 7 electrons not 8 so it is not a noble gas.

e.c of x:1s^22s^22p^63s^2

it has 8electrons so it is a noble gas.

e.c of y:1s^22s^23s^23p^64s^23d^2

it is not a noble gas as it has 2 electrons.

e.c of z:1s^22s^23s^23p^64s^23d^4

it is a noble gas .

hope it helps u.