A First-Order Reaction Has a Half-Life of 20

question 34

Multiple Choice

A first-order reaction has a half-life of 20.0 minutes. Starting with 1.00 *10²⁰ molecules of reactant at time t = 0, how many molecules remain unreacted after 100.0 minutes?

• A) 1.00 * 10⁴ molecules
• B) 2.00 * 10¹⁹ molecules
• C) 3.20 *10¹⁶ molecules
• D) 5.00 * 10²⁰ molecules
• E) None of these choices is correct.

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Definitions:

Opportunity Cost

The real cost of an item: what you must give up in order to get it.

Explicit Cost

Direct, out-of-pocket payments for expenses incurred in business operations, such as wages, rent, and materials.

Monetary Cost

The amount of money that must be paid or spent to acquire goods, services, or assets.

Implicit Cost

The opportunity costs that arise from using assets, resources, or funds in specific ways rather than the next best alternative.