The Reaction A $\to$ B Follows First-Order Kinetics with a Half-Life of 21

question 62

Multiple Choice

The reaction A $\to$ B follows first-order kinetics with a half-life of 21.7 hours.If the concentration of A is 0.023 M after 48.0 hours,what is the initial concentration of A?

• A) 0.0050 M
• B) 0.051 M
• C) 0.51 M
• D) 0.11 M
• E) 2.0 \(\times\) 10² M

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