A Certain First-Order Reaction a → B Is 25% Complete

question 122

Multiple Choice

A certain first-order reaction A → B is 25% complete in 42 min at 25°C. What is the half-life of the reaction?

• A) 21 min
• B) 42 min
• C) 84 min
• D) 120 min
• E) 101 min

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