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Ozone is a fascinating molecule composed of three oxygen atoms chemically bonded together, hence the formula \(\text{O}_3\). Unlike \(\text{O}_2\), which is the standard oxygen molecule we breathe, ozone plays a critical role in blocking harmful ultraviolet radiation from the Sun in the stratosphere, thus protecting life on Earth.The presence of ozone in the atmosphere is typically measured in terms of the number of molecules per given volume of air. This is important because the concentration of ozone directly corresponds to how effectively it blocks UV rays. In the provided exercise, we're looking at a scenario where ozone is under specific conditions of pressure and temperature, playing with these units to determine the quantity of ozone molecules in a set volume of air. Understanding ozone's behavior under different environmental conditions is key when evaluating its protective role in our atmosphere.

Calculating moles is a fundamental task in chemistry, especially when applying the Ideal Gas Law, represented by the formula \(PV = nRT\), where:

• \(P\) is pressure in atm
• \(V\) is volume in liters
• \(n\) is the number of moles
• \(R\) is the ideal gas constant \(0.0821 \text{ L·atm/K·mol}\)
• \(T\) is temperature in Kelvin

When calculating the number of moles of ozone in the atmosphere, as in the exercise above, it’s essential to ensure all units are consistent before plugging numbers into the formula. Once your units match, you can rearrange the equation to solve for \(n\), the number of moles, using the expression \(n = \frac{PV}{RT}\).Plugging in the given values for pressure, volume, and temperature, we calculated that there are \(4.84 \times 10^{-5}\) moles of ozone in \(1.0 \text{ L}\) of air under the given conditions. Moles serve as a bridge in chemistry—they enable conversion between atomic-scale entities like molecules and macroscopic-scale quantities used in lab settings.

A crucial tool in the world of chemistry, Avogadro's number \((6.022 \times 10^{23} \text{ molecules/mole})\) is pivotal in relating the macroscopic quantities of substances to their molecular scale counterpart. Named after the Italian scientist Amedeo Avogadro, this constant tells us how many entities (usually atoms or molecules) are in one mole of a substance.After calculating the moles of ozone using the Ideal Gas Law, we leverage Avogadro's number to find out the exact number of molecules present. Multiplying the number of moles by Avogadro’s number translates our moles into a sheer count of molecules. Through this calculation, we determined there were \(2.91 \times 10^{19}\) ozone molecules in \(1.0 \text{ L}\) of the stratosphere's air. This seamless conversion is essential to visualize and quantify the microscopic world within the realm of chemistry and the atmospheric sciences.