The U.S. Environmental Protection Agency (EPA) sets limits on healthful levels of air pollutants. The maximum level that the EPA considers safe for lead air pollution is 1.5 µg/m³. If your lungs were filled with air containing this level of lead, how many lead atoms would be in your lungs? (Assume a total lung volume of 5.50 L.)

Key Concepts

Molarity and Concentration

Molarity is a measure of concentration defined as the number of moles of solute per liter of solution. In this context, understanding how to convert the given concentration of lead (1.5 mg/m³) into moles is essential for calculating the number of lead atoms in the lungs. This involves using the molar mass of lead to relate mass to the number of moles.

Volume Conversion

To solve the problem, it is necessary to convert lung volume from liters to cubic meters, as the concentration of lead is given in mg/m³. Knowing that 1 L equals 0.001 m³ allows for the correct conversion, ensuring that the units are consistent when calculating the total mass of lead in the lungs.

Avogadro's Number

Avogadro's number (approximately 6.022 x 10²³) is the number of atoms or molecules in one mole of a substance. After determining the number of moles of lead in the lungs, this concept is crucial for converting moles to the actual number of lead atoms, providing a clear understanding of the scale of the pollution in terms of atomic quantity.