Practice problems

# Question
1 What is the density of 195 ml of a liquid that weighs 128 g ?
2 What is the weight in grams of 279 ml liquid, with a specific gravity of 0.94?
3 If a drug has specific gravity of 0.80. How many ml of drug do you need to get 50 g of drug?
4 What is the specific gravity of a 410 ml of liquid that weighs 394 g?
5 How many mg of a drug will be there in 5 ml of 0.30 % w/v timolol ophthalmic solution?
6 What is the volume of isopropyl alcohol required to make 580 ml of rubbing alcohol (70% v/v isopropyl alcohol)
7 How many grams of dextrose are required to prepare 3650 ml of 59 % solution?
8 Calculate the % w/v of 22 w/w % NaCl solution having a specific gravity of 1.16.
9 Calculate the % w/w of a solution prepared by dissolving 30 g of a drug in 4050 ml of water?
10 A pharmacist dispenses 30 ml of 17 % 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 : 289 as a percent strength.
12 Express 7.50 % as a ratio strength.
13 Calculate the milligrams of drug required to prepare 15 ml of a 1: 435 antiseptic solution.
14 How many milligrams of hexachlorophene should be used in compounding the following prescription?

Hexachlorophene 1 : 3100
Hydrophilic ointment ad 30 g
Sig. apply
15 Express 92 g in 550 ml as mg/ml.
16 Express 12 % w/v as mg/ml.
17 Express 1: 100 (w/v) as mg/ml.
18 Calculate the concentration of copper in ppm if 46 ml of tap water contains 2 X 10 -5 parts of copper.

Answers

The Answer to question 1 is: 0.66 g/ml

The Answer to question 2 is: 262.26 g

The Answer to question 3 is: 62.50 ml

The Answer to question 4 is: 0.96

The Answer to question 5 is: 15.00 mg

The Answer to question 6 is: 406.00 ml

The Answer to question 7 is: 2153.50 g

The Answer to question 8 is: 25.52 % w/v

The Answer to question 9 is: 0.74 % w/w

The Answer to question 10 is: 850 mg

The Answer to question 11 is: 0.35 %

The Answer to question 12 is: 1 : 13

The Answer to question 13 is: 34.48 mg

The Answer to question 14 is: 9.68 mg

The Answer to question 15 is: 167.27 mg/ml

The Answer to question 16 is: 120.00 mg/ml

The Answer to question 17 is: 10.00 mg/ml

The Answer to question 18 is: 0.43 ppm