Lewis structure of Si2H6

Step 1: Calculate total valence electrons

Si: Group IVA, 4 valence electrons; H: Group IA, 1 valence electron

Total valence electrons = 2 × 4 + 6 × 1 = 14 e?

Step 2: Determine the skeleton and central atoms

The two Si atoms are equivalent; use the Si–Si single bond as the core of the skeleton;

Each Si atom is bonded to 3 H atoms

Step 3: Connect all σ bonds and account for electrons

List of chemical bonds:

1 Si–Si single bond

6 Si–H single bonds

Total bonds = 7 single bonds

Bonding electrons:

7 × 2 = 14 e?

Remaining electrons:

14 ? 14 = 0 e?

No excess electrons; no lone pairs exist

Step 4: Octet check

Each Si: 4 single bonds (3 Si–H + 1 Si–Si), totaling 8 electrons; satisfies the octet rule

Each H: 1 single bond, 2 electrons; satisfies the hydrogen duet rule