Cinnamic alcohol is used mainly in perfurmery, particularly in soaps and cosmetics. Its molecular formula is C9H10O.
a. Calculate the percent composition by masss of C, H, and O in cinnamic alcohol.
b. How many molecules of cinnamic alchol are contained in a sample of mass 0.469 grams.
Please explain how to do this problem and provide the correct answers.
a) 45% C
50% H
5% 0
(I'm not sure what is meant with mass but this should be the percentage of how much of each element is present in the molecule...)
b) since molecular formula of cinnamic acid is C9H10O, its molecular mass is (9x12)+10+16 = 134.
This is the amount of g per mol.
So 0.469g has 0.035 mol.
Jazz. Can you give show me how to solve for cinnamic alcohol and not acid?
a. To calculate the percent composition by mass of C, H, and O in cinnamic alcohol, we need to determine the number of moles of each element present and then calculate the mass of each element.
1. Calculate the molar mass of cinnamic alcohol (C9H10O):
- The molar mass of carbon (C) is 12.01 g/mol.
- The molar mass of hydrogen (H) is 1.01 g/mol.
- The molar mass of oxygen (O) is 16.00 g/mol.
Molar mass of C9H10O = (9 * 12.01 g/mol) + (10 * 1.01 g/mol) + (1 * 16.00 g/mol) = 148.17 g/mol.
2. Calculate the mass of each element:
- Mass of carbon (C) = (9 * 12.01 g/mol) = 108.09 g.
- Mass of hydrogen (H) = (10 * 1.01 g/mol) = 10.10 g.
- Mass of oxygen (O) = (1 * 16.00 g/mol) = 16.00 g.
3. Calculate the percent composition by mass:
- Percent composition of C = (mass of C / molar mass of C9H10O) * 100% = (108.09 g / 148.17 g) * 100% = 72.98%.
- Percent composition of H = (mass of H / molar mass of C9H10O) * 100% = (10.10 g / 148.17 g) * 100% = 6.82%.
- Percent composition of O = (mass of O / molar mass of C9H10O) * 100% = (16.00 g / 148.17 g) * 100% = 10.81%.
Therefore, the percent composition by mass of C, H, and O in cinnamic alcohol is approximately 72.98% C, 6.82% H, and 10.81% O.
b. To determine the number of molecules of cinnamic alcohol in a sample of mass 0.469 grams, we need to use the concept of moles and Avogadro's number.
1. Calculate the number of moles of cinnamic alcohol:
- Moles = Mass / Molar mass.
- Moles = 0.469 g / 148.17 g/mol = 0.003166 mol (rounded to four decimal places).
2. Use Avogadro's number (6.022 x 10^23) to calculate the number of molecules in moles:
- Number of molecules = Moles * Avogadro's number.
- Number of molecules = 0.003166 mol * 6.022 x 10^23 molecules/mol = 1.904 x 10^21 molecules (rounded to three significant figures).
Therefore, there are approximately 1.904 x 10^21 molecules of cinnamic alcohol in a sample with a mass of 0.469 grams.
To calculate the percent composition by mass of C, H, and O in cinnamic alcohol, you need to determine the molar masses of C, H, and O, and then use these molar masses in the formula below:
Percent composition = (Molar mass of an element / Molar mass of the compound) x 100%
Let's calculate it step by step.
a. Percent composition by mass:
1. Molar mass of carbon (C): 12.01 g/mol
2. Molar mass of hydrogen (H): 1.01 g/mol
3. Molar mass of oxygen (O): 16.00 g/mol
Now, let's calculate the molar mass of cinnamic alcohol:
Cinnamic alcohol: C9H10O
Molar mass = (9 * Molar mass of C) + (10 * Molar mass of H) + (1 * Molar mass of O)
Molar mass of cinnamic alcohol = (9 * 12.01 g/mol) + (10 * 1.01 g/mol) + (16.00 g/mol)
Thus, the molar mass of cinnamic alcohol is approximately 148.18 g/mol.
Now, we can calculate the percent composition by mass:
1. Percentage of carbon (C) = (9 * 12.01 g/mol) / 148.18 g/mol * 100%
2. Percentage of hydrogen (H) = (10 * 1.01 g/mol) / 148.18 g/mol * 100%
3. Percentage of oxygen (O) = (1 * 16.00 g/mol) / 148.18 g/mol * 100%
By calculating the above expressions, we find the percent composition by mass of C, H, and O in cinnamic alcohol:
C: 72.80%
H: 6.46%
O: 20.74%
b. To calculate the number of molecules of cinnamic alcohol in a given mass of 0.469 grams, you first need to convert the mass to moles using the molar mass of cinnamic alcohol.
Number of moles = Mass / Molar mass
Number of moles of cinnamic alcohol = 0.469 g / 148.18 g/mol
Now, you can use Avogadro's number (6.022 × 10^23 molecules/mole) to convert moles to the number of molecules.
Number of molecules = Number of moles * Avogadro's number
Number of molecules of cinnamic alcohol = (0.469 g / 148.18 g/mol) * (6.022 × 10^23 molecules/mole)
By performing the above calculation, you will find the number of molecules of cinnamic alcohol contained in a sample with a mass of 0.469 grams.