If you used 6g of vitamin Z powder to make 20 ml of solution

If you used 6g of vitamin Z powder to make 20 ml of solution, what is the percentage concentration of this solution? 6g per 20 ml equivalent to 30g per 100 ml (multiply 20ml by s to get to 100 m) You work in a lab as a summer student. One of your tasks is to make sure that there is enough cell culture medium containing antibiotics to grow bacteria. one day you realize that there is only 5 ml of 10 percentage Antibiotic stock solution in the freezer. You decide to use it all to prepare the working culture medium with o 01 percentage antibiotic. In the lab there is plenty of growth medium without antibiotics. (Note: dilution in medium is like dilution in water). You remember the equation to make dilutions of stock solutions. You usually use this formula to calculate the required volume of a stock solution, but you realize it can apply here as we even though the unknown is the final volume. So, you make that dilution. Given that there each bacterial culture requires 200 ml of medium with 0.01 percentage antibiotics, how many cultures can you grow? Explain your reasoning. You are performing an enzymatic reaction to digest DNA and nothing works for you. You need to find out why. You added the enzyme and the DNA to the reaction yourself and you are sure you did it right. It must be the digestion buffer. The working solution for the digestion buffer should contain 400 mM Tris, pH 8.0 and 125 mM MgCl_2. First, you ask your colleague how he made the digestion buffer and he says: \"I mixed o.2 ml of 2M Tris, pH 8.0 stock solution o.25 ml of 5M MgCl_2 stock solution and completed the solution with 0.55 ml water to make a final volume of 1ml.\"

Solution

Answer:

(5) Each bacterial culture volume = 200mL, antibiotic = 0.01%

Total antibiotic present = 5mL of 10%

Amount of antibiotic required for each culture (200mL):

V1S1 = V2S2

10 * V1 = 200 * 0.01

So, V1 = 0.2 mL

Thus 0.2 mL from the antibiotic stock can be used for preparing 200mL of culture media.

Total volume of antibiotic present = 5mL

So, number of culture media that can be prepared = 5/0.2 = 25 culture media (200 mL each)