Question

Carbon cannot be used in the reduction of $Al₂O₃$ because ________.

• A. it is an expensive proposition
• B. the enthalpy of formation of $CO_{2}$ is more than that of $Al_{2}O_{3}$
• C. pure carbon is not easily available
• D. the enthalpy of formation of $Al_{2}O_{3}$ is too high

Hint:

Carbon cannot be used in the reduction of $Al2O3$ because ____.

Answer 1

The Correct Option is D

Step 1: Chemical Reactivity
Aluminum has a very high affinity for oxygen.
Step 2: Thermodynamic Analysis
The enthalpy of formation of $Al_{2}O_{3}$ is extremely high (very negative), meaning the Al-O bond is exceptionally strong.
Step 3: Comparison with Carbon
Carbon is not a strong enough reducing agent to overcome this high enthalpy and displace oxygen from alumina.
Hence, the Answer is: (D)