Calculating the Number of Moles of Na3PO4

Oct 13, 2025 by wbrum.org 22 views

**A 2.06 M Solution of Na3PO4: Calculating the Concentration of Na+ Ions in the Final Solution**

In this article, we will explore the concept of molarity and how to calculate the concentration of ions in a solution after mixing two different solutions. We will use the example of a 2.06 M solution of Na3PO4 and a 1.94 M solution of K2SO4 to demonstrate the steps involved in solving this type of problem.

Molarity is a measure of the concentration of a solution, expressed as the number of moles of solute per liter of solution. It is calculated using the formula:

Molarity (M) = moles of solute / liters of solution

For example, if we have a solution with a molarity of 2.06 M, it means that there are 2.06 moles of solute per liter of solution.

Calculating the Number of Moles of Na3PO4

To calculate the number of moles of Na3PO4 in the initial solution, we need to multiply the molarity of the solution by the volume of the solution in liters.

First, we need to convert the volume of the solution from milliliters (mL) to liters (L). There are 1000 mL in 1 L, so:

96.1 mL = 0.0961 L

Now, we can calculate the number of moles of Na3PO4:

moles of Na3PO4 = molarity x volume (in L) = 2.06 M x 0.0961 L = 0.198 M

Calculating the Number of Moles of K2SO4

Similarly, we can calculate the number of moles of K2SO4 in the second solution:

moles of K2SO4 = molarity x volume (in L) = 1.94 M x 0.147 L = 0.285 M

Calculating the Total Number of Moles of Na+ Ions

Since Na3PO4 is a salt that dissociates into three Na+ ions per molecule, the total number of moles of Na+ ions in the initial solution is three times the number of moles of Na3PO4:

moles of Na+ = 3 x moles of Na3PO4 = 3 x 0.198 M = 0.594 M

Similarly, since K2SO4 is a salt that dissociates into two K+ ions per molecule, the total number of moles of K+ ions in the second solution is two times the number of moles of K2SO4:

moles of K+ = 2 x moles of K2SO4 = 2 x 0.285 M = 0.57 M

Calculating the Total Number of Moles of Na+ Ions in the Final Solution

When we mix the two solutions, the total number of moles of Na+ ions in the final solution is the sum of the number of moles of Na+ ions in the initial solution and the number of moles of K+ ions in the second solution:

moles of Na+ in final solution = moles of Na+ in initial solution + moles of K+ in second solution = 0.594 M + 0.57 M = 1.164 M

Calculating the Concentration of Na+ Ions in the Final Solution

Finally, we can calculate the concentration of Na+ ions in the final solution by dividing the total number of moles of Na+ ions by the total volume of the final solution:

total volume of final solution = volume of initial solution + volume of second solution = 0.0961 L + 0.147 L = 0.2431 L

concentration of Na+ ions = moles of Na+ in final solution / total volume of final solution = 1.164 M / 0.2431 L = 4.79 M

Therefore, the concentration of Na+ ions in the final solution is 4.79 M.

In this article, we have demonstrated how to calculate the concentration of ions in a solution after mixing two different solutions. We have used the example of a 2.06 M solution of Na3PO4 and a 1.94 M solution of K2SO4 to illustrate the steps involved in solving this type of problem. By following these steps, we can calculate the concentration of Na+ ions in the final solution.

Q: What is molarity?

A: Molarity is a measure of the concentration of a solution, expressed as the number of moles of solute per liter of solution.

Q: How do I calculate the number of moles of solute in a solution?

A: To calculate the number of moles of solute, you need to multiply the molarity of the solution by the volume of the solution in liters.

Q: How do I calculate the concentration of ions in a solution after mixing two different solutions?

A: To calculate the concentration of ions in a solution after mixing two different solutions, you need to calculate the total number of moles of each ion in the final solution and then divide by the total volume of the final solution.

Q: What is the difference between molarity and molality?

A: Molarity is a measure of the concentration of a solution, expressed as the number of moles of solute per liter of solution. Molality, on the other hand, is a measure of the concentration of a solution, expressed as the number of moles of solute per kilogram of solvent.

Q: How do I convert milliliters to liters?

A: To convert milliliters to liters, you need to divide the number of milliliters by 1000.

Q: How do I calculate the total volume of a solution after mixing two different solutions?

A: To calculate the total volume of a solution after mixing two different solutions, you need to add the volumes of the two solutions.

Q: What is the significance of the concentration of ions in a solution?

A: The concentration of ions in a solution is important because it affects the chemical properties of the solution, such as its pH and reactivity.