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Option B: Drugs and Medicine: Exam Questions
1. Many drugs are taken orally
(a) State three other ways in which drugs may be taken by a patient.(3)
(b) State what is meant by the term side effect.(1)
2. One common type of drug taken orally is the antacid. Antacids such as sodium
hydrogen carbonate are taken to reduce stomach acidity.
(a) State the names of two metals, other than sodium, whose compounds are often
used in antacids.
(b) Give an equation for the neutralization of hydrochloric acid in the stomach by
sodium hydrogen carbonate.
(c) Explain how heartburn is caused.
(d) Explain why dimethicone is added to some antacids.
3. (a) State what is meant by the term analgesic. Explain the difference in the mode of
action of mild and strong analgesics.
(b) State the general names of the two functional groups attached to the benzene ring in a
molecule of aspirin. (See the page of structural structures.)
(c) The use of aspirin can have beneficial effects for the user, but can also produce some
unwanted side effects. State one beneficial effect and one unwanted side effect.
4. Morphine is a naturally occurring analgesic that can be converted into codeine. (Their
structures can be located on the structural structures page.)
(a) Calculate the difference in relative formula mass between morphine and
codeine.
(b) Explain what is meant by developing tolerance towards codeine and state why
this is dangerous.
5. Discuss two arguments against the legalization of cannabis.
.
6. Magnesium hydroxide and aluminium hydroxide can act as antacids.
(a) Write an equation for the reaction of hydrochloric acid with one of the above
antacids.
(b) Identify which antacid neutralizes the greater amount of hydrochloric acid if
0.1 mol of each antacid is used to neutralize the hydrochloric acid present in the
stomach .
(c) Give one reason why sodium hydroxide is not used instead of these antacids.
7. Penicillin G was the first antibiotic used to fight infections. The structure of this
antibiotic is on the molecular structures page.
(a) Determine the structural formula of penicillin G.
(b) State two reasons for modifying the side chain in penicillin G
(c) Describe the mode of action of penicillin in preventing the growth of bacteria.
(d) Discuss two effects of over prescription of penicillin to humans.
8. (a) Describe the differences in the ways that bacteria and viruses multiply.
(b) Outline two ways in which antiviral drugs work.
(c) Explain why effective treatment of AIDS with antiviral drugs is difficult.
(d) Explain how Tamiflu and Relenza reduce flu symptoms.
9. Refer to the last page when answering this question about analgesics.
(a) Describe the different ways in which mild and strong analgesics prevent pain.
Mild analgesics:
Strong analgesics:
(b) some mild analgesics are derivatives of salicylic acid. The structure of
salicylic acid is
(i) salicylic acid can be converted to aspirin. Give the formula of the group
that replaces one hydrogen atom in a molecule of salicylic acid in this
conversion
(ii) State the names of two functional groups present in acetaminophen
(paracetamol) and one functional group present in ibuprofen.
10. Antacids are used to neutralize our stomach.
(a) Write the neutralizing reaction between MgCO3 and our stomach acid. (2)
(b) Give the formula of one other antacid other than a group 2 antacid. (1)
(c) What is the purpose of adding alginates to antacids? (1)
11. Analgesics are used to control pain.
(a) How do strong analgesics work to control pain? (1)
(b) In addition to controlling pain, what are two other side effects seen from these
medications? (2)
(c) What is one major long term effect associated to these medicines? (1)
(d) How do mild analgesics work to control pain? (1)
(e) Give one disadvantage to using aspirin, and one disadvantage to using Tylenol
as a mild pain reliever. (2)
12. Each capsule of Solpadol®, a commercial analgesic, contains 500 mg of paracetamol
(acetaminophen) and 30 mg of codeine (in the form of codeine phosphate hemihydrate).
(a) Discuss the different modes of action of paracetamol (acetaminophen) and
codeine in relieving pain. (2)
(b) Diamorphine (heroin) is an even stronger painkiller than codeine. The
structures of codeine and diamorphine are given in table 20 of the Data Booklet.
Discuss, in terms of named functional groups, how the structure of diamorphine
differs from the structure of codeine. (3)
(c) State one specific reason why many doctors recommend paracetamol rather
than aspirin as a mild analgesic. (1)
(d) A normal aspirin tablet taken to relieve pain contains about 300 mg of aspirin.
Certain adults who are not in pain are recommend by doctors to take a smaller 75
mg dose of aspirin each day. State one reason for this recommendation. (1)
(e) Suggest a reason why aspirin and paracetamol are “over the counter” drugs but
in many countries Solpadol® must be prescribed by a doctor.
13. Maalox® manufactures several different types of antacid. Maalox® Extra Strength is a
suspension. One teaspoon (5.00 cm3) contains 400mg of magnesium hydroxide,
Mg(OH)2, 306 mg of aluminium hydroxide, Al(OH)3, and 40.0 mg of simethicone.
Maalox® Extra Strength with Anti-gas comes in tablet form. Each tablet contains 1000mg
of calcium carbonate, CaCO3, and 60.0 mg of simethicone.
(a) State the equations for the reactions of magnesium hydroxide, aluminium
hydroxide and calcium carbonate with hydrochloric acid. (3)
Magnesium hydroxide:
Aluminium hydroxide:
Calcium carbonate:
(b) Stomach acid approximates to 1.00 x 10-2 mol dm-3 hydrochloric acid.
Assuming that simethicone does not react with acid, determine the volume, in
dm3, of stomach acid neutralized by:
(i) one teaspoon (5.00 cm3) of Maalox® Extra Strength. (2)
(ii) one tablet of Maalox® Extra Strength with Anti-gas. (2)
(c) Suggest the function of the simethicone present in both antacids. (1)