Practice problems

# Question
1 What is the density of 209 ml of a liquid that weighs 23 g ?
2 What is the weight in grams of 36 ml liquid, with a specific gravity of 2.86?
3 If a drug has specific gravity of 1.20. How many ml of drug do you need to get 5 g of drug?
4 What is the specific gravity of a 255 ml of liquid that weighs 437 g?
5 How many mg of a drug will be there in 20 ml of 0.40 % w/v timolol ophthalmic solution?
6 What is the volume of isopropyl alcohol required to make 330 ml of rubbing alcohol (70% v/v isopropyl alcohol)
7 How many grams of dextrose are required to prepare 2470 ml of 39 % solution?
8 Calculate the % w/v of 1 w/w % NaCl solution having a specific gravity of 1.004.
9 Calculate the % w/w of a solution prepared by dissolving 40 g of a drug in 100 ml of water?
10 A pharmacist dispenses 70 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 : 452 as a percent strength.
12 Express 8.50 % as a ratio strength.
13 Calculate the milligrams of drug required to prepare 65 ml of a 1: 40 antiseptic solution.
14 How many milligrams of hexachlorophene should be used in compounding the following prescription?

Hexachlorophene 1 : 4600
Hydrophilic ointment ad 65 g
Sig. apply
15 Express 12 g in 100 ml as mg/ml.
16 Express 42 % w/v as mg/ml.
17 Express 1: 2500 (w/v) as mg/ml.
18 Calculate the concentration of copper in ppm if 72 ml of tap water contains 3 X 10 -5 parts of copper.

Answers

The Answer to question 1 is: 0.11 g/ml

The Answer to question 2 is: 102.96 g

The Answer to question 3 is: 4.17 ml

The Answer to question 4 is: 1.71

The Answer to question 5 is: 80.00 mg

The Answer to question 6 is: 231.00 ml

The Answer to question 7 is: 963.30 g

The Answer to question 8 is: 1.00 % w/v

The Answer to question 9 is: 28.57 % w/w

The Answer to question 10 is: 50 mg

The Answer to question 11 is: 0.22 %

The Answer to question 12 is: 1 : 11

The Answer to question 13 is: 1625.00 mg

The Answer to question 14 is: 14.13 mg

The Answer to question 15 is: 120.00 mg/ml

The Answer to question 16 is: 420.00 mg/ml

The Answer to question 17 is: 0.40 mg/ml

The Answer to question 18 is: 0.42 ppm