Practice problems

# Question
1 What is the density of 185 ml of a liquid that weighs 190 g ?
2 What is the weight in grams of 8 ml liquid, with a specific gravity of 3.56?
3 If a drug has specific gravity of 2.40. How many ml of drug do you need to get 85 g of drug?
4 What is the specific gravity of a 105 ml of liquid that weighs 442 g?
5 How many mg of a drug will be there in 10 ml of 0.45 % w/v timolol ophthalmic solution?
6 What is the volume of isopropyl alcohol required to make 500 ml of rubbing alcohol (70% v/v isopropyl alcohol)
7 How many grams of dextrose are required to prepare 4550 ml of 16 % solution?
8 Calculate the % w/v of 24 w/w % NaCl solution having a specific gravity of 1.18.
9 Calculate the % w/w of a solution prepared by dissolving 90 g of a drug in 3650 ml of water?
10 A pharmacist dispenses 15 ml of 1 % w/v ibuprofen suspension, which is to be taken as 2 teaspoonful’s per day. How many milligrams of ibuprofen are contained per teaspoonful?
11 Express 1 : 316 as a percent strength.
12 Express 9.00 % as a ratio strength.
13 Calculate the milligrams of drug required to prepare 90 ml of a 1: 455 antiseptic solution.
14 How many milligrams of hexachlorophene should be used in compounding the following prescription?

Hexachlorophene 1 : 4500
Hydrophilic ointment ad 45 g
Sig. apply
15 Express 13 g in 700 ml as mg/ml.
16 Express 26 % w/v as mg/ml.
17 Express 1: 3500 (w/v) as mg/ml.
18 Calculate the concentration of copper in ppm if 99 ml of tap water contains 2 X 10 -5 parts of copper.

Answers

The Answer to question 1 is: 1.03 g/ml

The Answer to question 2 is: 28.48 g

The Answer to question 3 is: 35.42 ml

The Answer to question 4 is: 4.21

The Answer to question 5 is: 45.00 mg

The Answer to question 6 is: 350.00 ml

The Answer to question 7 is: 728.00 g

The Answer to question 8 is: 28.32 % w/v

The Answer to question 9 is: 2.41 % w/w

The Answer to question 10 is: 50 mg

The Answer to question 11 is: 0.32 %

The Answer to question 12 is: 1 : 11

The Answer to question 13 is: 197.80 mg

The Answer to question 14 is: 10.00 mg

The Answer to question 15 is: 18.57 mg/ml

The Answer to question 16 is: 260.00 mg/ml

The Answer to question 17 is: 0.29 mg/ml

The Answer to question 18 is: 0.20 ppm