Online Test — Chemistry in Everyday Life
20 Questions • 15 min • Chapter MCQ
15:00
Question 1 of 20
The two most important molecular targets for drug action are:
lipids and sugars
enzymes and receptors
vitamins and minerals
DNA and water
Explanation: Drugs act mainly on enzymes (catalytic proteins) and receptors (membrane proteins that transmit chemical messages).
Question 2 of 20
A drug that mimics the natural messenger and switches a receptor on is called a/an:
antagonist
inhibitor
agonist
preservative
Explanation: An agonist activates the receptor like the natural chemical; an antagonist binds but blocks it.
Question 3 of 20
Cimetidine and ranitidine relieve acidity by blocking:
H1 receptors
H2 receptors
enzymes
sodium pumps
Explanation: They are H2-receptor blockers that prevent histamine from stimulating stomach-acid secretion.
Question 4 of 20
Which of the following is a non-narcotic analgesic?
morphine
heroin
aspirin
codeine
Explanation: Aspirin is a non-addictive, non-narcotic analgesic; morphine, heroin and codeine are narcotic analgesics.
Question 5 of 20
Penicillin was the first antibiotic and is an example of a:
broad-spectrum bacteriostatic drug
narrow-spectrum bactericidal drug
tranquilizer
disinfectant
Explanation: Penicillin G is narrow-spectrum (acts on a few bacteria) and bactericidal (kills bacteria).
Question 6 of 20
Antibiotics that only inhibit the growth of bacteria are described as:
bactericidal
bacteriostatic
broad-spectrum
narcotic
Explanation: Bacteriostatic antibiotics (e.g. erythromycin, tetracycline) inhibit growth; bactericidal ones kill bacteria.
Question 7 of 20
A 0.2% solution of phenol acts as a/an ____ while a 1% solution acts as a/an ____.
disinfectant; antiseptic
antiseptic; disinfectant
analgesic; antacid
antibiotic; antiseptic
Explanation: The milder 0.2% solution is safe on living tissue (antiseptic); the stronger 1% solution is a disinfectant.
Question 8 of 20
Dettol, an antiseptic, is a mixture of:
chloroxylenol and terpineol
phenol and water
iodine and alcohol
boric acid and salt
Explanation: Dettol is a mixture of chloroxylenol and terpineol, used on living tissue.
Question 9 of 20
Antifertility drugs (oral contraceptives) chiefly contain synthetic:
insulin and adrenaline
oestrogen and progesterone
thyroxine and calcitonin
testosterone and cortisol
Explanation: Oral contraceptives use synthetic oestrogen (ethynylestradiol) and progesterone (norethindrone) to suppress ovulation.
Question 10 of 20
Equanil and barbiturates are examples of neurologically active drugs called:
analgesics
antibiotics
tranquilizers/hypnotics
antiseptics
Explanation: Equanil is a tranquilizer and barbiturates are hypnotics; both act on the central nervous system.
Question 11 of 20
Which artificial sweetener decomposes on heating and so is used only in cold foods?
saccharin
sucralose
aspartame
alitame
Explanation: Aspartame is unstable to heat, so it cannot be used for cooking.
Question 12 of 20
The artificial sweetener about 2000 times sweeter than sucrose is:
saccharin
aspartame
sucralose
alitame
Explanation: Alitame is a very high-potency sweetener, about 2000 times sweeter than cane sugar.
Question 13 of 20
Sodium benzoate is added to soft drinks and sauces as a:
sweetener
preservative
antioxidant
detergent
Explanation: Sodium benzoate (C6H5COONa) is a chemical preservative that inhibits micro-organisms.
Question 14 of 20
BHA and BHT are used in fatty foods because they act as:
sweeteners
antioxidants
antibiotics
soaps
Explanation: Antioxidants are oxidised in preference to the food and so prevent fats from turning rancid.
Question 15 of 20
Soap is prepared by the saponification of a fat or oil with:
dilute HCl
sodium hydroxide
ammonia
calcium chloride
Explanation: Saponification is the alkaline hydrolysis of fat/oil by NaOH to give soap and glycerol.
Question 16 of 20
Soaps do not work well in hard water because they form an insoluble scum with:
Na+ and K+ ions
Ca2+ and Mg2+ ions
Cl- ions
H+ ions
Explanation: Calcium and magnesium ions precipitate soap as an insoluble scum; detergent salts of these ions are soluble.
Question 17 of 20
A detergent is biodegradable if its hydrocarbon chain is:
highly branched
straight (unbranched)
aromatic
very long
Explanation: Bacteria can degrade straight-chain detergents; highly branched chains resist degradation and pollute water.
Question 18 of 20
In a micelle formed by soap in water, the hydrocarbon tails point:
outward toward the water
inward, away from the water
in all directions equally
toward other heads
Explanation: The hydrophobic tails turn inward (toward grease/away from water) while the hydrophilic heads face the water.
Question 19 of 20
Classification of drugs most useful to a medicinal chemist designing new drugs is by:
pharmacological effect
chemical structure
molecular target
physical appearance
Explanation: Grouping drugs by the biomolecule (target) they bind guides the design of new drugs for that target.
Question 20 of 20
A drug with a large therapeutic index is:
very toxic
relatively safe
ineffective
always an antibiotic
Explanation: A large (toxic dose)/(effective dose) ratio means a wide safety margin, so the drug is relatively safe.