Indicate the concentration of each ion present in the solution formed by mixing: (a) 42.0 mL of 0.170 M NaOH with 37.6 mL of 0.400 M NaOH.

Verified step by step guidance

1. Calculate the moles of NaOH in the first solution using the formula: \( \text{moles} = \text{volume (L)} \times \text{molarity (M)} \).
2. Calculate the moles of NaOH in the second solution using the same formula.
3. Add the moles of NaOH from both solutions to find the total moles of NaOH.
4. Calculate the total volume of the mixed solution by adding the volumes of the two solutions.
5. Determine the concentration of NaOH in the mixed solution by dividing the total moles of NaOH by the total volume in liters.

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 calculating the concentration of ions in a solution after mixing different volumes and concentrations of solutions. Understanding how to convert volumes and molarities into moles allows for accurate determination of ion concentrations in the final mixture.

Dilution

Dilution refers to the process of reducing the concentration of a solute in a solution, typically by adding more solvent. When two solutions are mixed, the total volume increases, which affects the concentration of the ions present. The dilution equation, M1V1 = M2V2, can be applied to find the new concentration after mixing, where M is molarity and V is volume.

Ion Concentration Calculation

Calculating ion concentration involves determining the total moles of each ion present in the mixed solution and dividing by the total volume of the solution. In this case, since both solutions contain NaOH, which dissociates completely into Na+ and OH- ions, it is essential to calculate the moles of NaOH from each solution and then find the concentration of Na+ and OH- ions in the final volume.