Respuesta :
Answer : The percentage by mass of carbon in hydrocortisone valerate is 69.95 %.
Solution :
The molecular formula is [tex]C_{26}H_{38}O_6[/tex].
The molar mass of Carbon = 12 g/mole
The molar mass of Hydrogen = 1 g/mole
The molar mass of Oxygen = 16 g/mole
First we have to calculate the mass of one mole of [tex]C_{26}H_{38}O_6[/tex].
In this molecule, there are 26 carbon atom, 38 hydrogen atom and 6 oxygen atom.
Mass of 26 moles of carbon = 26 moles × 12 g/mole = 312 g
Mass of 38 moles of hydrogen = 38 moles × 1 g/mole = 38 g
Mass of 6 moles of oxygen = 6 moles × 16 g/mole = 96 g
Total mass of one mole of [tex]C_{26}H_{38}O_6[/tex] = 312 + 38 + 96 = 446 g
Now we have to calculate the percent by mass of carbon in hydrocortisone valerate.
%[tex]\text{ mass of carbon}=\frac{\text{ mass of carbon}}{\text{ total mass}}\times 100= \frac{312g}{446g}\times 100=69.95[/tex]%
Therefore, the percentage by mass of carbon in hydrocortisone valerate is 69.95 %.
