Consider the following reaction: SiC (hexagonal) → SiC (cubic), ΔG = –0.598 kcal/mol (–2.50 kJ/mol) at 25°C. Explain why SiC (hexagonal) lasts for a long period of time even though the reaction is spontaneous. 

• A. The reaction must have a high activation energy.
• B. The reaction does not occur naturally.
• C. The reaction must have a low activation energy.
• D. The reaction must occur at temperatures lower than 25°C.

Answer: (A)