Answer:
3 × 10²⁰ molecules C₉H₃O₄
Explanation:
Step 1: Define
Avagadro's Number: 6.02 × 10²³ atoms, molecules, formula units, etc.
Molar Mass C - 12.01 g/mol
Molar Mass H - 1.01 g/mol
Molar Mass O - 16.00 g/mol
Molar Mass C₉H₃O₄ - 175.12 g/mol
Step 2: Use Dimensional Analysis
[tex]0.1 \hspace{3} g \hspace{3} C_9H_3O_4(\frac{1 \hspace{3} mol \hspace{3} C_9H_3O_4}{175.12 \hspace{3} g \hspace{3} C_9H_3O_4} )(\frac{6.02(10)^{23} \hspace{3} molecules \hspace{3} C_9H_3O_4}{1 \hspace{3} mol \hspace{3} C_9H_3O_4} )[/tex] = 3.43764 × 10²⁰ molecules C₉H₃O₄
Step 3: Simplify
We are give 1 sig fig.
3.43764 × 10²⁰ molecules C₉H₃O₄ ≈ 3 × 10²⁰ molecules C₉H₃O₄
