High School

Select the correct answer.

The atomic mass of potassium is 39.1. What is the mass of [tex]$6.02 \times 10^{23}$[/tex] atoms of potassium?

A. [tex]39.1 \, \text{mg}[/tex]

B. [tex]39.1 \, \text{g}[/tex]

C. [tex]39.1 \, \text{kg}[/tex]

D. [tex]6.02 \times 39.1 \, \text{mg}[/tex]

E. [tex]6.02 \times 39.1 \, \text{g}[/tex]

Answer :

To determine the mass of [tex]\(6.02 \times 10^{23}\)[/tex] atoms of potassium, we can use the concept of a mole. A mole is a unit in chemistry that is used to express amounts of a chemical substance.

Here's a step-by-step breakdown:

1. Understand the concept of a mole: Avogadro's number, which is [tex]\(6.02 \times 10^{23}\)[/tex], represents the number of atoms, ions, or molecules in one mole of a substance.

2. Relate atomic mass to moles: The atomic mass of potassium is 39.1 grams per mole. This means that one mole of potassium atoms has a mass of 39.1 grams.

3. Determine the mass of the given number of atoms: Since [tex]\(6.02 \times 10^{23}\)[/tex] atoms is exactly one mole, the mass of these atoms is simply the atomic mass of potassium, which is 39.1 grams.

Therefore, the mass of [tex]\(6.02 \times 10^{23}\)[/tex] atoms of potassium is 39.1 grams.

So, the correct answer is:
B. [tex]\(39.1 \, \text{g}\)[/tex]