Final answer:
The number of moles of carbon in 83.36 g of valine is calculated by first finding the molar mass of valine and then using that to determine the moles of valine. Multiplying that result by 5 (the number of carbon atoms in valine) gives the moles of carbon, which is approximately 3.559 moles.
Step-by-step explanation:
To determine the number of moles of carbon in 83.36 g of valine, which has the formula C5H11NO2, we first need to calculate the molar mass of valine. Valine consists of 5 carbon atoms, 11 hydrogen atoms, 1 nitrogen atom, and 2 oxygen atoms. The molar mass of valine can be calculated as follows:
- 5 moles of carbon (C) × 12.01 g/mol = 60.05 g/mol
- 11 moles of hydrogen (H) × 1.008 g/mol = 11.088 g/mol
- 1 mole of nitrogen (N) × 14.01 g/mol = 14.01 g/mol
- 2 moles of oxygen (O) × 16.00 g/mol = 32.00 g/mol
Add these together to get the molar mass of valine:
60.05 g/mol (C) + 11.088 g/mol (H) + 14.01 g/mol (N) + 32.00 g/mol (O) = 117.148 g/mol (valine)
Now, to find out how many moles of valine are in 83.36 g, we use the following formula:
Moles of valine = mass of valine (g) / molar mass of valine (g/mol)
Moles of valine = 83.36 g / 117.148 g/mol ≈ 0.7118 moles
Since each mole of valine has 5 moles of carbon, we multiply the moles of valine by 5 to get the moles of carbon:
Moles of carbon in valine = 0.7118 moles × 5 = 3.559 moles of carbon