A sample of the male sex hormone testosterone, C19H28O2, contains 4.09 1021 hydrogen atoms
What is the mass of this sample in grams?
i got 0.0697g but its wrong
To find the mass of the sample, we need to calculate the molar mass of testosterone and then multiply it by the number of moles present in the sample.
First, let's calculate the molar mass of testosterone (C19H28O2):
C: 19 atoms x 12.01 g/mol = 228.19 g/mol
H: 28 atoms x 1.01 g/mol = 28.28 g/mol
O: 2 atoms x 16.00 g/mol = 32.00 g/mol
Total molar mass of testosterone:
228.19 g/mol + 28.28 g/mol + 32.00 g/mol = 288.47 g/mol
Now, we can calculate the number of moles in the sample using Avogadro's number:
Number of moles = (number of hydrogen atoms) / (Avogadro's number)
Number of moles = 4.09 x 10^21 / 6.022 x 10^23 = 0.006789 moles
Finally, we can find the mass of the sample by multiplying the number of moles by the molar mass:
Mass = 0.006789 moles x 288.47 g/mol = 1.96 grams
Therefore, the correct mass of the sample is approximately 1.96 grams, not 0.0697 grams.
To calculate the mass of the sample in grams, we need to determine the molar mass of testosterone and then multiply it by the number of moles in the sample.
1. Start by finding the molar mass of testosterone (C19H28O2). To do this, multiply the atomic masses of each element by their respective subscripts and sum them up:
- Carbon (C): 12.01 g/mol x 19 = 228.19 g/mol
- Hydrogen (H): 1.01 g/mol x 28 = 28.28 g/mol
- Oxygen (O): 16.00 g/mol x 2 = 32.00 g/mol
Adding these values together: 228.19 + 28.28 + 32.00 = 288.47 g/mol
2. Now, we need to find the number of moles in the sample. We can use Avogadro's number (6.022 x 10^23) to convert the number of atoms to moles:
Number of moles = Number of atoms / Avogadro's number
Number of atoms = 4.09 x 10^21
Avogadro's number = 6.022 x 10^23
Number of moles = (4.09 x 10^21) / (6.022 x 10^23) ≈ 6.79 x 10^-3 moles
3. Finally, multiply the number of moles by the molar mass to find the mass of the sample:
Mass = Number of moles x Molar mass
Mass = (6.79 x 10^-3 moles) x (288.47 g/mol) ≈ 1.96 grams
Therefore, the mass of the given sample of testosterone is approximately 1.96 grams, not 0.0697 grams.