2. A. During Part I of the water Analysis series, you prepared a Stock solution
ID: 706583 • Letter: 2
Question
2. A. During Part I of the water Analysis series, you prepared a Stock solution of Phosphate ion containing 50.0 mg P/L. In the second part of this experiment, you will use this Stock solution to prepare Standard solutions to be used to make a calibration plot. As described in the background information for this experiment, the concentration of Phosphorus in these standards should be between 0 mg /L (Solution A)and 0.6 mg/L (Solution C). A. Describe HOW you are going to prepare Solution C, which must contain 0.3 mg P/L. Assume you are going to use a 250-mL volumetric flask for this preparation. Be sure to include necessary CALCULATIONS! B. Another standard (Solution B) should have the concentration between 0 and 0.6 mg P/L value for this concentration and show calculations to be used for preparation of 250 ml. of Solution B Choose aExplanation / Answer
2.)A) To create a solution of 0.3 mg of P/L from a stock solution of 50 mg of P/L
we will use the formulae M1V1=M2V2 ; Where M1=Stock solution concentration ; M2=Final solution concentration ; V1=Stock solution Volume ;V2=Final solution Volume;
Hence the workout is
50*V1=0.3*0.25 ==>V1=0.0015 L=1.5 ml
to make up the rest of the solution we need to add distilled water. The volume of distilled water to be added is 250-1.5=248.5 ml
Hence to make a solution of 0.3 mg of P/L from a stock solution of 50 mg of P/L we need to add 1.5 ml of 50 mg of P/L to 248.5 ml of distilled water.
B)
To create a solution of 0.2 mg of P/L from a stock solution of 50 mg of P/L
we will use the formulae M1V1=M2V2 ; Where M1=Stock solution concentration ; M2=Final solution concentration ; V1=Stock solution Volume ;V2=Final solution Volume;
Hence the workout is
50*V1=0.2*0.25 ==>V1=0.001 L=1.0 ml
to make up the rest of the solution we need to add distilled water. The volume of distilled water to be added is 250-1.0=249 ml
Hence to make a solution of 0.2 mg of P/L from a stock solution of 50 mg of P/L we need to add 1.0 ml of 50 mg of P/L to 249 ml of distilled water.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.