Exercise -Hydroo ortisono is a storoid (corticosteroid)medicine, 0.75 gram Hydrocortisono (C_(21)H_(30)O_(5)) is used to produce one tube of a pharmacotical cream Calculato the number of Oxygen (O) atoms in 075 gram Hydrocortisone. M(14 yirocortisone)=362.47g/mol

To calculate the number of oxygen atoms in 0.75 grams of hydrocortisone, we need to follow these steps:<br /><br />1. **Determine the molar mass of hydrocortisone (C\(_{21}\)H\(_{30}\)O\(_{5}\))**:<br /> - Carbon (C): 21 atoms × 12.01 g/mol = 252.21 g/mol<br /> - Hydrogen (H): 30 atoms × 1.008 g/mol30.24 g/mol<br /> - Oxygen (O): 5 atoms × 16 g/mol = 80.00 g/mol<br /><br /> Total molar mass = 252.21 g/mol + 30.24 g/mol + 80.00 g/mol = 362.45 g/mol<br /><br />2. **Calculate the number of moles of hydrocortisone in 0.75 grams**:<br /> \[<br /> \text{Moles of hydrocortisone} = \frac{\text{Mass}}{\text{Molar mass}} = \frac{0.75 \text{ g}}{362.45 \text{ g/mol}} \approx 0.00207 \text{ moles}<br /> \]<br /><br />3. **Determine the number of oxygen atoms in the calculated moles**:<br /> - Each mole of hydrocortisone contains 5 moles of oxygen atoms.<br /> \[<br /> \text{Moles of oxygen atoms} = 0.00207 \text{ moles of hydrocortisone} \times 5 \text{ moles of O atoms/mole of hydrocortisone} = 0.01035 \text{ moles of O atoms}<br /> \]<br /><br />4. **Convert the moles of oxygen atoms to the number of oxygen atoms**:<br /> - Use Avogadro's number (6.022 × 10\(^{23}\) atoms/mol) to find the number of oxygen atoms.<br /> \[<br /> \text{Number of oxygen atoms} = 0.01035 \text{ moles} \times 6.022 \times 10^{23} \text{ atoms/mole} \approx 6.22 \times 10^{21} \text{ oxygen atoms}<br /> \]<br /><br />Therefore, there are approximately \(6.22 \times 10^{21}\) oxygen atoms in 0.75 grams of hydrocortisone.