Chemical analysis reveals capsaicin to contain 71.0% of carbon, 8.60% hydrogen, 15.8% oxygen and 4.60% nitrogen.
a) Determine the empirical formula of capsaicin
b) Each molecule contains one atom of nitrogen. What is the molecular formula of capsaicin?
I figured out the empirical formula but I got stuck on the molecular formula.
The chemachles will change color and make sprarks.
that doesn't answer the question.
what is the molecular formula of capsaicin and please show work
To determine the empirical formula of capsaicin, we need to find the simplest whole number ratio of the atoms present in the compound.
a) Determining the empirical formula:
Given the percentages of carbon (C), hydrogen (H), oxygen (O), and nitrogen (N) in capsaicin, we can convert these percentages into grams. Let's assume we have 100 grams of capsaicin for simplicity.
1. Calculate the number of grams for each element:
- Carbon (C): 71.0% of 100g = 71g
- Hydrogen (H): 8.60% of 100g = 8.60g
- Oxygen (O): 15.8% of 100g = 15.8g
- Nitrogen (N): 4.60% of 100g = 4.60g
2. Convert grams to moles:
- Carbon (C): Divide the mass (in grams) by the molar mass of carbon (12.01 g/mol): 71g / 12.01 g/mol ≈ 5.91 mol C
- Hydrogen (H): Divide the mass (in grams) by the molar mass of hydrogen (1.01 g/mol): 8.60g / 1.01 g/mol ≈ 8.52 mol H
- Oxygen (O): Divide the mass (in grams) by the molar mass of oxygen (16.00 g/mol): 15.8g / 16.00 g/mol ≈ 0.99 mol O
- Nitrogen (N): Divide the mass (in grams) by the molar mass of nitrogen (14.01 g/mol): 4.60g / 14.01 g/mol ≈ 0.33 mol N
3. Determine the simplest ratio of moles:
- Divide all the moles by the smallest number of moles (0.33 mol N, in this case):
C: 5.91 mol C / 0.33 mol N ≈ 17.9
H: 8.52 mol H / 0.33 mol N ≈ 25.8
O: 0.99 mol O / 0.33 mol N ≈ 3.00
N: 0.33 mol N / 0.33 mol N = 1
Therefore, the empirical formula of capsaicin is C18H26O3N.
b) To determine the molecular formula, we need to know the molar mass of the compound.
The molar mass of the empirical formula C18H26O3N can be calculated using the atomic masses of carbon, hydrogen, oxygen, and nitrogen. The molar masses are approximately:
- Carbon (C): 12.01 g/mol
- Hydrogen (H): 1.01 g/mol
- Oxygen (O): 16.00 g/mol
- Nitrogen (N): 14.01 g/mol
Summing up the molar masses of all the elements in the empirical formula:
C: 18 × 12.01 g/mol = 216.18 g/mol
H: 26 × 1.01 g/mol = 26.26 g/mol
O: 3 × 16.00 g/mol = 48.00 g/mol
N: 1 × 14.01 g/mol = 14.01 g/mol
Therefore, the molar mass of the empirical formula C18H26O3N is approximately 304.45 g/mol.
If we divide the molar mass of the molecular formula by the molar mass of the empirical formula, we can determine the ratio between them:
Molar mass of molecular formula / Molar mass of empirical formula = Molecular formula ratio
Let's assume the molar mass of the molecular formula is indicated as "X."
X / 304.45 g/mol = Molecular formula ratio
Since we know that the empirical formula contains one atom of nitrogen per molecule, the molecular formula ratio should also be equal to 1.
Therefore, we can conclude that the molecular formula of capsaicin is the same as the empirical formula, which is C18H26O3N.
Hence, the molecular formula of capsaicin is C18H26O3N.