Concentration

Question

A dermatologist prescribed the following on a prescription 

Rx

Sulphur 2%

Salicylic acid 6%

Soft paraffin

                                          Mitte: 60g  ointment

 

 

You are required to compound this mixture,  how much of each ingredient would you use. Remember to calculate the amount of ointment base?

 

 

 

2. You are the head pharmacy technician at get well hospital . In the pharmacy that you work you have distilled water , bulk powder, carbamazepine tablets 200mg, carbamazepine 30% and carbamazepine 1%. When you get to work you find out that 3.6 gallon bottle of 2 % w/v stock carbamazepine suspension you normally keep on hand has finished and you need to refill the bottle.  How many carbamazepine 200mg tablets must be used to make enough suspension to refill the bottle? 

 

 

3. How many milliters of 3% w/v solution and 7% w/v solution should be used to prepare two 2 quarts of a 3.5% w/v solution? 

 

 

Please show all working 

Answer 1

Sulphur 2% x 60 g = 1.2 g sulfur
Salicylic acid 6% x 60 g = 3.6 g SA
Soft paraffin qs to 60 g (60 g - 1.2 g - 3.6 g) = 55.2 g

 

Try #2 and #3 and if you can't do them, ask again.