Silicon valence electrons — periodic table recall How many valence electrons does a silicon (Si) atom possess?

Introduction / Context:Semiconductor bonding and band structure originate from the valence electron configuration. Silicon, the workhorse of microelectronics, forms covalent bonds using its outer-shell electrons.

Given Data / Assumptions:

• Element: Silicon (Z = 14).
• Electronic configuration (ground state): 1s² 2s² 2p⁶ 3s² 3p².

Concept / Approach:Valence electrons are those in the outermost shell participating in bonding. For Si, the outer shell is n = 3 with 3s² 3p², totaling 4 valence electrons. This tetra-valence enables sp³ covalent bonding in the diamond cubic crystal structure.

Step-by-Step Solution:Identify outer shell: n = 3.Count electrons in 3s and 3p: 2 + 2 = 4.Hence, valence electrons = 4.

Verification / Alternative check:Group IV (14) elements in the periodic table (C, Si, Ge, Sn) all have 4 valence electrons, consistent with tetrahedral bonding.

Why Other Options Are Wrong:2, 1, or 0 contradict the electron configuration; 6 would suit Group 16 elements, not Group 14.

Common Pitfalls:Confusing total electrons with valence electrons; overlooking shell structure.

Final Answer:4