Question

You have a summer research internship, and your preceptor asks you to prepare a barium solution for use in the lab. The recipe is as follows:

Barium 0.178% w/v solution 1ml

Purified Water qs 100ml

Calculate the concentration of barium in the mixture. Express in ppm (parts per million or ____g/1,000,000ml)

2: A compounding pharmacist has a supply of 0.03% w/w tacrolimus ointment, used in the treatment of psoriasis. He receives a prescription for 180g of a 0.1% w/w tacrolimus ointment. With the goal of using the lower strength ointment before it expires, he plans to add tacrolimus powder to obtain the desired concentration of API. How should he prepare 180g of the ointment? Use the alligation method for this problem

Answer 1

The concentration of barium in the barium solution is 17.8 ppm.

Step-by-step explanation:

The concentration of barium in the barium solution can be calculated by dividing the mass of barium by the total volume of the solution, and then converting it to parts per million (ppm). In this case, the mass of barium is 0.178% of 1 mL, which is 0.00178 g. The total volume of the solution is 100 mL. To calculate the concentration in ppm, we divide the mass of barium by the total volume of solution and multiply by 1,000,000:

Concentration of barium = (0.00178 g / 100 mL) x 1,000,000 = 17.8 ppm