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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Definitions:

Body Mass Index

Body Mass Index (BMI) is a numerical value derived from a person's weight and height, used as an indicator of whether they have a healthy body weight for their height.

Normal Weight

A weight classification based on body mass index (BMI) that is considered within the healthy range for a person's height.

Body Mass Index

A numerical measurement calculated from height and weight that is used to assess whether a person is underweight, normal weight, overweight, or obese.

Overweight

A condition characterized by an individual having more body fat than is optimally healthy for their height and build.