Answer: ns²np².
- A ns²np¹
- B ns²np²
- C ns²np³
- D ns²np⁴
Correct answer: B. ns²np²
Explanation: Group 14 elements have two electrons in the outermost p subshell: ns²np².
Diamond's rigid 3D tetrahedral network makes it the hardest natural material, while graphite's flat hexagonal sheets are held together only by weak forces, letting them slide past each other (used as a lubricant and in pencils).
Concept context
Covers the Boron family (Group 13: B, Al) and the Carbon family (Group 14: C, Si, Ge, Sn, Pb). Key topics include Lewis acid behaviour of BF₃, borax bead test, silicates, silicones, allotropes of carbon, and trends in properties down the group.