Ethylene glycol, C2H6O2, is a colorless liquid used as auto-mobile antifreeze. If the density at 20 °C of a 4.028 m solu- tion of ethylene glycol in water is 1.0241 g/mL, what is the molarity of the solution? The molar mass of ethylene glycol is 62.07 g/mol

Key Concepts

Molarity

Molarity is a measure of concentration defined as the number of moles of solute per liter of solution. It is expressed in units of moles per liter (mol/L). To calculate molarity, you need to know the amount of solute in moles and the total volume of the solution in liters. This concept is crucial for understanding how concentrated a solution is and for performing stoichiometric calculations.

Density

Density is the mass of a substance per unit volume, typically expressed in grams per milliliter (g/mL) or kilograms per cubic meter (kg/m³). In this context, the density of the solution allows us to convert the mass of the solution into volume, which is necessary for calculating molarity. Understanding density is essential for relating mass and volume in solution chemistry.

Molality

Molality is a concentration measure defined as the number of moles of solute per kilogram of solvent. It is expressed in moles per kilogram (mol/kg). In this problem, the solution's molality is given, which is important for determining the amount of solute present in a specific mass of solvent. Molality is particularly useful in colligative property calculations and when temperature changes affect volume.