Which of the following noble gases does not have an octer of electrons in its outermost shell ?

Correct Answer - C Valency of A is 3 and that of X is (8-6), i.e.2

Correct Answer - D CO molecule does not follow octet rule

Correct Answer - C Configuration of `Cl^-` ion is `1s^2 2s^2 2p^6 3s^2 3p`

Correct Answer - A Helium (He) being the lightest among the noble gases, has this property which is not shown by other members of the family.

Correct Answer - A Argon checks the reactivity of metals towards oxidation by providing an inert atmosphere.

It is given that, `E_(K)=35.2keV,E_(L)=5.25keV,E_(M)=0.55 keV` `rArr" " E_(K)-E_(L)=(hc)/(lambda_(K_(A_(alpha))))=hv_(K_(alpha))` `rArr(35.2-5.25)xx10^(3)xx1.6xx10^(-19)=6.6xx10^(-34)v_(K_(alpha))` `rArr" " v_(K_(alpha))=(29.95xx10^(3)xx1.6xx10^(-19))/(6.6xx10^(-34))=7.2xx10^(-34)Hz` Similarly, `E_(K)-E_(M)=hv_(K_(beta))` `rArr" " v_(K_(beta))=((35.2-0.55)xx10^(3)xx1.63xx10^(-19))/(6.6xx10^(-34))=8.4xx10^(18)Hz` Also, `E_(L)-E_(M)=hv_(k_(alpha))` `rArr" " ((5.25-0.55)xx10^(3)xx1.6xx10^(-19))/(6.6xx10^(-34))=1.1xx10^(18)Hz`

Correct Answer - A (a) The electronic configuration of Cu, Th, Cs and K are Cu(29) = 2, 8,, 18, 1 `Cu^(+) = 2,8,18` Th(90)= 2, 8, 18, 32, 18, 10,...

`B^(+3)rarrHe` `Al^(+3)rarrNe` `underset(Ge^(+4))overset(Ge^(+3)).}rarrns^(2),np^(6),nd^(10)` pseudo inert gas configuration

Option : A. 1 

Option : B. 4, 5, 6 or 7