Question

which of the following molecules include a central atom that does not obey the octet rule? i. pf3 ii. no2 iii. sf4 iv. co2 o i, ii, iii and iv o ii only o i and iv only o i, iii and iv only o ii and iii only

Explanation:

The octet rule states that atoms tend to gain, lose, or share electrons to have eight electrons in their outer - shell. In $NO_2$, nitrogen has an odd number of electrons and cannot achieve a full octet. In $SF_4$, sulfur has 10 electrons around it (expanded octet). $PF_3$ has phosphorus with a full octet and $CO_2$ has carbon with a full octet.

Answer:

II and III only