Answer:
Explanation:
<u>First question: a. Find the empirical formula of the compound</u>
<u>1) Calculate the number of moles of every element that is in the hydrocarbon</u>
- number of moles = mass in grams / atomic mass
- Carbon: 12.00 g / 12.01 g/mol = 0.999 mol
- Hydrogen: 1.5 g / 1.008 g/mol = 1.488 mol
<u>2) Divide by the least number of moles, to find the mol ratio:</u>
- Carbon: 0.999 mol / 0.999 mol = 1
- Hydrogen: 1.488 mol / 0.999 mol = 1.5
<u>3) Multiply by 2 to obtain whole numbers:</u>
Thus, the mole ratio is 2 : 3, and the empirical formula is C₂ H₃
<u>Second question: b. What is the molecular formula?</u>
<u>1) Find the mass of the empirical formula:</u>
- C: 2 × 12.01 g/mol = 24.02 g/mol
- H: 3 × 1.008 g/mol = 3.024 g/mol
Molar mass of the empirical formula = 24.02 g/mol + 3.024 g/mol = 27.044 g/mol ≈ 27.04 g/mol
<u>2) Find the number of times that the empirical mass is contained in the molar mass</u>:
- 54.10 g/mol / 27.04 g / mol = 2
<u>3) Multiply every atom in the empirical formula by the ratio 2:</u>