EASY
Diploma
IMPORTANT
Earn 100

"In the field of observation, chance favours the prepared mind"- Louis Pasteur. Using the discovery of penicillin as an example, discuss the influence of an open-minded attitude on our perceptions.

Important Questions on Medicinal Chemistry

EASY
Diploma
IMPORTANT

A well-known brand of antacids contains 0.160 g of aluminium hydroxide and 0.105 g of magnesium carbonate in each tablet.

State the separate equations for the reactions of aluminium hydroxide and magnesium carbonate with hydrochloric acid.

EASY
Diploma
IMPORTANT

A well-known brand of antacids contains 0.160 g of aluminium hydroxide and 0.105 g of magnesium carbonate in each tablet. The tablets also contain alginic acid and sodium hydrogen carbonate. The function of the sodium hydrogen carbonate is to react with alginic acid to form sodium alginate. State the function of the sodium alginate produced.

EASY
Diploma
IMPORTANT
A suspension of magnesium hydroxide in water, known as "milk of magnesia" is a common antacid. A  2.0 cm3 sample of the suspension has a density of 1.15 kg dm-3 and can neutralise 15.8 cm3 of 0.400 mol dm-3 hydrochloric acid. Calculate the mass percentage of magnesium hydroxide in the suspension.
EASY
Diploma
IMPORTANT
Two substances commonly used in antacid tablets are magnesium hydroxide and aluminium hydroxide. Explain why alginates and dimethicone are often included in antacid tablets?
EASY
Diploma
IMPORTANT
The acidity of gastric juice can be temporarily reduced by antacids or controlled at the cellular level by certain drugs, such as renitidine (an H2-receptor antagonist), omeprazole, and esomeprazole (proton pump inhibitors). Each of these methods has benefits and disadvantages. Discuss how we choose between different approaches that can be utilised to solve the same problem. 
EASY
Diploma
IMPORTANT
An acetate buffer was prepared from 500 cm3 of 0.100 mol dm-3 ethanoic acid (pKa=4.76) and 16.4 g of solid sodium acetate. Assuming that the addition of sodium acetate does not affect the solution volume, calculate the pH of this buffer solution.
EASY
Diploma
IMPORTANT
State the pH range in which acetate buffers can be used.
MEDIUM
Diploma
IMPORTANT
An acetate buffer was prepared from 500 cm3 of 0.100 mol dm-3 ethanoic acid (pKa=4.76) and 16.4 g of solid sodium acetate. Deduce the molecular and ionic equations that show the buffer action of this solution when a small amount of hydrochloric acid is added and when a small amount of sodium hydroxide is added.