Question

A student obtains 100 mL of a 0.0002442 M solution of AgNO 3 (silver nitrate). He labels this "solution #1". He then pipets 5 mL of Solution #1 into a 50 mL volumetric flask and dilutes to the mark with water. He labels this "Solution #2." He then pipets 10 mL of Solution #1 into a 250 mL volumetric flask and dilutes to the mark with water. This is "Solution #3". Finally, the prepares "Solution #4" by pipetting 18 mL of solution #3 into a 50 mL volumetric flask and dilutes to the mark with water. Draw relational pictures to illustrate the relationship between the original solution and all of the diluted solutions that the student prepared. What is the concentration of silver nitrate in Solution #4?

Answer 1

Answer: The concentration of Silver Nitrate in solution # 4 is 3.5x10-6 M

Explanation:

When calculating the concentration of a dilute solution, we use the equation:

C1V1 = C2V2

Where C1 = concentration of the known solution

V1= amount of know solution

C2= new concentration

V2= capacity of the flask

Keep in mind that solution #2 is not related to the preparation of solutions #3 y #4, so the concentration of #2 is irrelevant.

For calculating the concentration of solution #4 , we first calculate the concentration of the solution #3, that comes from the solution #1.

1. Calculating concentration solution #3

• C1V1 = C3V3
• C3= (0.0002442 M * 10mL) / 250mL  
• C3= 9.8X10-6M      

      2. Calculating concentration solution #4

• C3V3 = C4V4
• C4= (9.8X10-6M *18mL) / 50mL
• C4= 3.5X10-6 M