What is the molarity of each ion in a solution prepared by dissolving 0.550 g of Na2SO4, 1.188 g of Na3PO4, and 0.223 g of Li2SO4 in water and diluting to a volume of 100.00 mL?

Verified step by step guidance

1. First, calculate the number of moles of each compound. The molar mass of Na2SO4 is approximately 142.04 g/mol, the molar mass of Na3PO4 is approximately 163.94 g/mol, and the molar mass of Li2SO4 is approximately 109.94 g/mol. Use these values to convert the mass of each compound to moles.
2. Next, calculate the number of moles of each ion in the solution. Na2SO4 dissociates into 2 Na+ ions and 1 SO4^2- ion, Na3PO4 dissociates into 3 Na+ ions and 1 PO4^3- ion, and Li2SO4 dissociates into 2 Li+ ions and 1 SO4^2- ion. Multiply the number of moles of each compound by the number of each ion it produces to find the total number of moles of each ion.
3. Then, calculate the total volume of the solution in liters. Since molarity is defined as moles of solute per liter of solution, it's important to convert the volume from milliliters to liters. There are 1000 milliliters in a liter, so divide the volume in milliliters by 1000 to convert to liters.
4. Now, calculate the molarity of each ion. Molarity is defined as the number of moles of solute divided by the volume of the solution in liters. Divide the number of moles of each ion by the volume of the solution in liters to find the molarity of each ion.
5. Finally, remember that the molarity of each ion is the concentration of that ion in the solution. It tells you how many moles of that ion are present in one liter of the solution. This is a measure of the 'strength' or 'concentration' of that ion in the solution.

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 moles per liter (mol/L) and is crucial for understanding how much of a substance is present in a given volume of solution. To calculate molarity, one must first determine the number of moles of solute by dividing the mass of the solute by its molar mass, and then divide by the volume of the solution in liters.

Dissociation of Ionic Compounds

Ionic compounds, such as Na2SO4 and Na3PO4, dissociate into their constituent ions when dissolved in water. This dissociation is essential for calculating the molarity of each ion in the solution. For example, Na2SO4 dissociates into 2 Na⁺ ions and 1 SO4²⁻ ion, while Na3PO4 dissociates into 3 Na⁺ ions and 1 PO4³⁻ ion. Understanding the stoichiometry of these dissociations allows for accurate calculations of ion concentrations.

Calculating Total Volume

When preparing a solution, the total volume after dilution is critical for determining the molarity of the ions. In this case, the final volume is given as 100.00 mL, which must be converted to liters (0.100 L) for molarity calculations. It is important to ensure that all solutes are accounted for in the final volume to accurately reflect the concentration of each ion in the solution.