The Hexaammine Cobalt(III)ion Is Very Unstable in Acidic Aqueous Solution

question 86

Multiple Choice

The hexaammine cobalt(III) ion is very unstable in acidic aqueous solution: [Co(NH₃) ₆]³⁺(aq) + 6 H₃O⁺(aq) → [Co(H₂O) ₆]⁴⁺(aq) + 6 NH₄⁺(aq)
However,solutions of hexaammine cobalt(III) can be stored in acidic solution for months without noticeable decomposition.Which statement below about the equilibrium constant and the activation energy for the reaction is true?

• A)K_eq < 10³ and E_a is very small.
• B)K_eq > 10³ and E_a is very small.
• C)K_eq < 10³ and E_a is very large.
• D)K_eq > 10³ and E_a is very large.

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