Answer:
There are 0.00390 moles of Barium in 2.35 × 10²¹ atoms of Ba.
General Formulas and Concepts:
Stoichiometry
- Mole ratio
- Avogadro's Number: 6.023 × 10²³ atoms/moles/molecules/formula units/etc.
- Dimensional analysis
Explanation:
Step 1: Define
Identify.
2.35 × 10²¹ atoms Ba
Step 2: Convert
- [Dimensional Analysis] Set up: [tex]\displaystyle 2.35 \cdot 10^{21} \ \text{atoms Ba} \bigg( \frac{1 \ \text{mol Ba}}{6.022 \cdot 10^{23} \ \text{atoms Ba}} \bigg)[/tex]
- [Dimensional Analysis] Evaluate: [tex]\displaystyle \displaystyle 2.35 \cdot 10^{21} \ \text{atoms Ba} \bigg( \frac{1 \ \text{mol Ba}}{6.022 \cdot 10^{23} \ \text{atoms Ba}} \bigg) = 0.003902[/tex]
- [Sig Figs] Round: [tex]\displaystyle \displaystyle 2.35 \cdot 10^{21} \ \text{atoms Ba} \bigg( \frac{1 \ \text{mol Ba}}{6.022 \cdot 10^{23} \ \text{atoms Ba}} \bigg) \approx 0.00390[/tex]
Topic: AP Chemistry
Unit: Stoichiometry
