Question

determine the number of moles in 1.49e23 formula units of cacl₂.

Explanation:

Step1: Recall Avogadro's number

Avogadro's number $N_A = 6.022\times 10^{23}\text{ formula units/mol}$.

Step2: Calculate moles

Use the formula $n=\frac{N}{N_A}$, where $N = 1.49\times 10^{23}$ formula units. So $n=\frac{1.49\times 10^{23}}{6.022\times 10^{23}}$.

Answer:

$0.247$