How many oxygen atoms are present in 2.28 moles of nitric acid, \( \mathrm{HNO}_{3} \) ? a \( 1.37 \times 10^{24} \mathrm{O} \) atoms b \( 4.12 \times 10^{24} \mathrm{O} \) atoms c \( 7.29 \times 10^{23} \mathrm{O} \) atoms d \( 4.58 \times 10^{23} \mathrm{O} \) atoms

To find the number of oxygen atoms in 2.28 moles of nitric acid (\( \mathrm{HNO}_{3} \)), first note that each molecule of nitric acid contains 3 oxygen atoms. Therefore, the total number of moles of oxygen can be calculated by multiplying the moles of nitric acid by the number of oxygen atoms per molecule: \[ \text{Oxygen moles} = 2.28 \, \text{moles} \times 3 = 6.84 \, \text{moles of O} \] Next, to convert moles of oxygen to atoms, use Avogadro's number (\( 6.022 \times 10^{23} \, \text{atoms/mole} \)): \[ \text{Oxygen atoms} = 6.84 \, \text{moles O} \times 6.022 \times 10^{23} \, \text{atoms/mole} \approx 4.12 \times 10^{24} \, \text{O atoms} \] So, the answer is b \( 4.12 \times 10^{24} \mathrm{O} \) atoms. --- Did you know that nitric acid has a fascinating history? It was known to alchemists and was made by distilling saltpeter and sulfuric acid! This powerful acid has played a significant role in the development of modern chemistry and is crucial for creating fertilizers and explosives. If you're ever unsure about these types of calculations, remember to break it down step-by-step! The most common mistake is forgetting to multiply by the number of specific atoms in the compound (in this case, 3 for oxygen). So always double-check how many of the atoms you need for accuracy!