Answer:
1.53 × 10²³ molecules As₂O₃
Explanation:
Step 1: Define
Diarsenic Trioxide - As₂O₃
Avagadro's number: 6.02 × 10²³ atoms, molecules, formula units, etc.
Step 2: Use Dimensional Analysis
[tex]0.254 \hspace{3} mol \hspace{3} As_2O_3(\frac{6.02(10)^{23} \hspace{3} molecules \hspace{3} As_2O_3}{1 \hspace{3} mol \hspace{3} As_2O_3} )[/tex] = 1.52908 × 10²³ molecules As₂O₃
Step 3: Simplify
We have 3 sig figs.
1.52908 × 10²³ molecules As₂O₃ ≈ 1.53 × 10²³ molecules As₂O₃
