Describe how to prepare each solution from the dry solute and the solvent. b. 125 g of 0.100 m NaNO₃

Key Concepts

Molarity

Molarity (M) is a measure of concentration defined as the number of moles of solute per liter of solution. It is crucial for preparing solutions, as it allows chemists to quantify how much solute is needed to achieve a desired concentration. In this case, a 0.100 M solution of NaNO3 means there are 0.100 moles of NaNO3 in every liter of the final solution.

Calculating Moles

To prepare a solution, it is essential to calculate the number of moles of solute required. The number of moles can be determined using the formula: moles = mass (g) / molar mass (g/mol). For NaNO3, the molar mass is approximately 85 g/mol, so to find out how many moles are in 125 g, one would divide 125 g by 85 g/mol.

Dilution and Solution Preparation

Preparing a solution involves dissolving the calculated amount of solute in a specific volume of solvent. For a 0.100 M NaNO3 solution, after determining the required moles from the mass, the solute should be added to a volumetric flask with a portion of solvent, mixed until dissolved, and then diluted to the final volume with additional solvent to ensure the correct concentration.