Conductivity values (S m⁻¹) at 298 K: 2.1×10³, 1.0×10⁻¹⁶, 1.2×10⁻³, 3.91, 1.5×10⁻², 1×10⁻⁷, 1.0×10³ Find number of condu…

Classification based on conductivity:

Conductors: conductivity ≈ 10³ S m⁻¹ or higher
Semiconductors: intermediate (10⁻⁶ to 10² approx)
Insulators: very low (≈10⁻¹⁰ or less)

2.1×10³ → conductor
1.0×10⁻¹⁶ → insulator
1.2×10⁻³ → semiconductor
3.91 → this is relatively high → conductor (ionic conductor)
1.5×10⁻² → semiconductor
1×10⁻⁷ → semiconductor/insulator borderline
1.0×10³ → conductor

Electrolytes (like aqueous ionic solutions) with conductivity in range of ~1–10 S m⁻¹ are also considered conductors, not semiconductors.

Thus:

Conductors:
2.1×10³
3.91
1.0×10³
1.5×10⁻² (weak electrolyte → still conductor)

Total = 4