Residues of the herbicide atrazine (C₈H₁₄ClN₅) in water can be detected at concentrations as low as 0.050 µg/L. Express this concentration of atrazine in the following units: (b) Molarity

Verified step by step guidance

1. insert step 1> Determine the molar mass of atrazine (C8H14ClN5) by adding the atomic masses of all the atoms in the formula.
2. insert step 2> Convert the concentration from mg/L to g/L by dividing by 1000.
3. insert step 3> Use the molar mass to convert the concentration from g/L to moles/L (molarity) by dividing the mass concentration by the molar mass.
4. insert step 4> Ensure the units are consistent throughout the calculation to maintain accuracy.
5. insert step 5> The result from step 3 will give you the molarity of atrazine in the solution.

Key Concepts

Molarity

Molarity (M) is a measure of concentration defined as the number of moles of solute per liter of solution. It is commonly used in chemistry to express the concentration of a substance in a solution. To convert from mass concentration (mg/L) to molarity, one must know the molar mass of the solute, which allows for the calculation of moles from the given mass.

Molar Mass

Molar mass is the mass of one mole of a substance, typically expressed in grams per mole (g/mol). It is calculated by summing the atomic masses of all the atoms in a molecule. For atrazine (C8H14ClN5), the molar mass is essential for converting the concentration from mg/L to moles per liter, which is necessary for expressing the concentration in molarity.

Unit Conversion

Unit conversion is the process of converting a quantity expressed in one set of units to another set of units. In this context, it involves converting the concentration of atrazine from milligrams per liter (mg/L) to molarity (M). This requires using the molar mass of atrazine to relate the mass of the solute to the number of moles, facilitating the conversion to the desired concentration unit.