Practice problems

# Question
1 What is the density of 38 ml of a liquid that weighs 246 g ?
2 What is the weight in grams of 449 ml liquid, with a specific gravity of 3.76?
3 If a drug has specific gravity of 2.80. How many ml of drug do you need to get 55 g of drug?
4 What is the specific gravity of a 90 ml of liquid that weighs 345 g?
5 How many mg of a drug will be there in 5 ml of 0.10 % w/v timolol ophthalmic solution?
6 What is the volume of isopropyl alcohol required to make 940 ml of rubbing alcohol (70% v/v isopropyl alcohol)
7 How many grams of dextrose are required to prepare 4080 ml of 39 % solution?
8 Calculate the % w/v of 26 w/w % NaCl solution having a specific gravity of 1.19.
9 Calculate the % w/w of a solution prepared by dissolving 10 g of a drug in 1200 ml of water?
10 A pharmacist dispenses 85 ml of 7 % 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 : 708 as a percent strength.
12 Express 0.30 % as a ratio strength.
13 Calculate the milligrams of drug required to prepare 15 ml of a 1: 205 antiseptic solution.
14 How many milligrams of hexachlorophene should be used in compounding the following prescription?
℞
Hexachlorophene 1 : 1800
Hydrophilic ointment ad 55 g
Sig. apply
15 Express 95 g in 250 ml as mg/ml.
16 Express 81 % w/v as mg/ml.
17 Express 1: 1200 (w/v) as mg/ml.
18 Calculate the concentration of copper in ppm if 37 ml of tap water contains 2 X 10 -5 parts of copper.

Answers

The Answer to question 1 is: 6.47 g/ml

The Answer to question 2 is: 1688.24 g

The Answer to question 3 is: 19.64 ml

The Answer to question 4 is: 3.83

The Answer to question 5 is: 5.00 mg

The Answer to question 6 is: 658.00 ml

The Answer to question 7 is: 1591.20 g

The Answer to question 8 is: 30.94 % w/v

The Answer to question 9 is: 0.83 % w/w

The Answer to question 10 is: 350 mg

The Answer to question 11 is: 0.14 %

The Answer to question 12 is: 1 : 333

The Answer to question 13 is: 73.17 mg

The Answer to question 14 is: 30.56 mg

The Answer to question 15 is: 380.00 mg/ml

The Answer to question 16 is: 810.00 mg/ml

The Answer to question 17 is: 0.83 mg/ml

The Answer to question 18 is: 0.54 ppm