Answer :
Answer: Look Down
Explanation: You are absolutely correct! Many elements in the third row and beyond of the periodic table can form compounds in which the central atom is surrounded by more than 8 electrons according to the Lewis structure model. This is due to a concept called expanded octet or hypervalency.
Here's why elements in the third row and beyond can violate the octet rule:
d orbitals: In the second row of the periodic table, elements only have s and p orbitals in their valence shell. These orbitals can hold a maximum of 8 electrons (4 in s and 4 in p). However, elements from the third row onwards have access to d orbitals in their valence shell. These d orbitals can hold an additional 10 electrons.
Larger atomic radii: Elements in the third row and beyond have larger atomic radii compared to those in the second row. This increased space allows them to accommodate more electrons around the central atom.
Common examples of elements in the third row and beyond that exhibit expanded octet include:
Sulfur (S): Can form SF6 (sulfur hexafluoride) with six fluorine atoms surrounding the central sulfur atom.
Phosphorus (P): Can form PCl5 (phosphorus pentachloride) with five chlorine atoms surrounding the central phosphorus atom.
Chlorine (Cl): In some exceptional cases, chlorine can also violate the octet rule, for example, in ClO4- (chlorate ion).
Lewis structures are often used to depict these expanded octet molecules, although sometimes resonance structures are needed to accurately represent the bonding.
It's important to note that the octet rule is a helpful guideline but not an absolute rule. Elements in the third row and beyond can often form stable compounds with more than 8 electrons around the central atom due to the availability of d orbitals and larger atomic radii.