In which of the following situations is the mole concept most likely to be used?

• A. Calculating the number of atoms in a given mass of an element
• B. Measuring the temperature of a solution
• C. Determining the color of a compound
• D. Estimating the pressure of a gas in a container

Answer: (A)

Verified step by step guidance

1. Understand that the mole concept is a fundamental counting unit in chemistry used to relate the amount of substance to the number of particles (atoms, molecules, ions, etc.).
2. Recognize that the mole concept is most relevant when you need to convert between mass and number of particles, such as calculating the number of atoms in a given mass of an element.
3. Identify that measuring temperature, determining color, or estimating pressure do not directly involve counting particles or converting between mass and number of entities, so the mole concept is not typically used in these cases.
4. Recall the key formula relating moles to number of particles: \(\text{Number of particles} = \text{moles} \times 6.022 \times 10^{23}\) (Avogadro's number).
5. Also remember the relationship between mass and moles: \(\text{moles} = \frac{\text{mass}}{\text{molar mass}}\), which is essential for calculating the number of atoms from a given mass.