You are required to make l0mL of a 0.5M solution of HCl. Your stock solution of

Question

You are required to make l0mL of a 0.5M solution of HCl. Your stock solution of HCl is 90M. Using distilled water ((dH_2O) as a solvent, how much of each component will you need to make the desired final solution? You need to make 500mL of 7H9(+) media with 1X ADN and 30ug/mL of the antibiotic kanamycin. Your stock solutions are 10X ADN and 30mg/mL of kanamycin. The solvent is distilled water. How much of each component will you need to make the desired final solution? I You want to make the following buffer: 5% glucose, 100 mM tris and 10 mM EDTA in a final volume of 300ml. Your stock solutions are 20% glucose, 1M tries and 0.5M EDTA. The solvent is distilled water. In the space provided determine how much of each you will add to make the desired buffer.

Explanation / Answer

1. If we apply the following formula we can get the desired solution

C1V1 = C2 V2

C1 initial concentration , 90M

V1 initial volume ( volume to be pipette ) , ?

C2 final concentration , 0.5M

V2 final volume , 10ml

V1 =( C2 × V2 )/ C2 =( 0.5 × 10 )/90= 0.055ml

Thus 0.055 ml of 90M stock HCl solution should be pipette out and transfered into 10 ml volumetric flask and make up for 100 ml by distilled water.

0.055 ml is less volume to be pipette , so it is better to prepare a10 time diluted (9M) solution from the stock.From this solution we can prepare the desired solution.

2.Apply the anove formula

C1V1 = C2V2

for ADN ,

V1 = (1X × 500ml) / 10X = 50ml

For kanamycine

V1 =(0.030mg/ml× 500ml)/30mg/ml = 0.5ml

Therefore, 50ml of 10 ADN and 0.5 ml of kanamycine should be pipette out from their stock solution and transfer it into the 500ml volumetric flask and makeup it for 500ml with distilled water.

3.Apply the formula for each component

C1V1 = C2 V2

For glucose

V1 =( 5 × 300ml)/ 20% = 75ml

For Tris

V1 = (0.1M × 300ml)/1 = 30ml

For EDTA

V1 = (0.01M × 300ml)/0.5M = 6ml

So, pipette out 75ml of glucose solution,30ml of tris solution and 6ml of EDTA solution from their respective stock solutions and these into 300ml volumetric flask and make up for 300ml by distilled water.

  

  

Related Questions

Navigate

• Browse (All)
• Browse Y
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.