Which statement best describes a mole?

Step 1: Define the Problem

Identify the key components of the question that need to be addressed: Understanding the concept of a mole in chemistry.

Step 2: Break Down the Problem

Divide the problem into smaller, manageable parts:

• Determine what a mole represents in chemistry.
• Identify the significance of a mole in chemical calculations.

Step 3: Apply Relevant Concepts

Use appropriate academic theories or formulas to solve each part of the problem:

• A mole is a fundamental unit in chemistry used to express amounts of a chemical substance.
• It is defined as the amount of substance containing the same number of entities (atoms, molecules, ions, etc.) as there are atoms in 12 grams of pure carbon-12.

Step 4: Analysis, Verify and Summarize

Analysis each part in details if necessary carry out the calculations by steps. Verify the calculations result and summarize the findings:

• The number of entities in a mole is known as Avogadro's number, which is approximately $6.022 \times 10^{23}$.
• This concept allows chemists to count particles by weighing them and is crucial for stoichiometry in chemical reactions.

Final Answer

A mole is a unit in chemistry that represents $6.022 \times 10^{23}$ entities of a substance, allowing for the quantification and comparison of chemical reactions.