What is the main reason that is generally given to explain the fact that the second row element carbon forms discrete molecules, CO₂, with two oxygen atoms, but the third row element silicon forms a network solid, (SiO₂)_n, when it bonds to two oxygen atoms?

Question

Quizplus · Accepted Answer

The larger size of third row elements like silicon makes it difficult to form stable pi bonds, which are necessary for molecules to form discrete structures like carbon dioxide (CO2). Instead, silicon forms a network solid when bonded to oxygen because of its ability to form strong covalent bonds with multiple neighboring atoms, creating a three-dimensional network. This is not related to the electronegativity difference between the two elements or the position of oxygen on the periodic table.

What Is the Main Reason That Is Generally Given to Explain