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State Board · Class 11 · Chemistry

Lesson 16: Chemistry in Everyday Life

7 concepts · 56 practice questions with answers · Free to read

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Drugs: definition, classification and targets

From daily life

A headache tablet or a fever syrup is a chemical acting at a specific site in the body.

Simple definition

A drug is a chemical giving a biological response in small amounts. Chemotherapy treats disease with chemicals. Classification: by action, chemical structure or molecular target.

Drug classesClassification of drugs (by action)Analgesicspain: aspirin, morphineAntipyreticsfever: paracetamolAntibioticsbacteria: penicillinAntacidsacidity: Mg(OH)₂, ranitidineAntihistaminesallergy: brompheniramineTranquilisersanxiety: equanil, valiumAntimicrobialsantiseptics/disinfectantsAntifertilitynorethindrone

In the figure : Main drug classes.

Drug targetDrug and target (enzyme / receptor)Competitive inhibitorenzymeDdrug blocks the active siteAllostericenzymeDbinds elsewhere, changes the shapeReceptor: protein; agonist = triggers response, antagonist = blockse.g. ranitidine blocks H₂ receptors ⇒ less HCl secretionMorphine: opioid receptor agonist ⇒ pain relief

In the figure : Drug and target.

Rule 1: Drug–target interaction — Targets: enzymes or receptors (proteins). Enzyme inhibitors: competitive (block the active site) or allosteric.

  • Easy : Competitive: the drug competes with the substrate.
  • Medium : Receptor agonist: triggers a response (morphine).
  • Exam-type : Antagonist: blocks (ranitidine).

Rule 2: Classes by action — Analgesics, antipyretics, antibiotics, antacids, antihistamines, tranquilisers, antimicrobials, antifertility drugs.

  • Easy : Aspirin: pain + fever.
  • Medium : Penicillin: bacteria.
  • Exam-type : Norethindrone: contraception.

Rule 3: Drug action and safety — Dose matters; too much is toxic; self-medicating with antibiotics builds resistance.

  • Easy : Excess paracetamol harms the liver.
  • Medium : A half-finished course ⇒ resistant bacteria.
  • Exam-type : Not without a doctor's advice.

Reasoning: how does a competitive inhibitor work?

  • Step 1: The drug resembles the substrate in shape.
  • Step 2: It binds the active site.
  • Step 3: The substrate cannot bind ⇒ the reaction slows.

CET level (MCQ)

  • CET 1) A receptor is a? 1) carbohydrate 2) protein 3) lipid 4) acid — Answer: 2).
  • CET 2) Chemotherapy is? 1) treating disease with chemicals 2) diet 3) surgery 4) yoga — Answer: 1).

Real-life use: Diagnosis, treatment, cancer chemotherapy.

Remember

Targets = enzymes/receptors; competitive = active site; agonist activates, antagonist blocks.

Common mistake

Thinking a drug is only a tablet; syrups, injections and ointments count too.

CET trap

Antibiotics do not work on viruses.

Shortcut

Memory clue: "agonist = on, antagonist = off".

Spot the difference

ItemCompetitiveAllosteric
Bindingactive siteanother site
Effectcompeteschanges shape

Practice questions

Easy
  1. 1What is a drug?
  2. 2What is chemotherapy?
  3. 3Name drug targets.
Medium
  1. 4Explain a competitive inhibitor.
  2. 5Agonist versus antagonist?
  3. 6Why is a half course dangerous?
Challenging
  1. 7List five drug classes.
  2. 8Why not antibiotics for viruses?
Show answers (try them yourself first)
  1. 1A chemical eliciting a biological response.
  2. 2Treating disease with chemicals.
  3. 3Enzymes and receptors.
  4. 4Blocks the active site.
  5. 5Activates / blocks.
  6. 6Resistant bacteria.
  7. 7Analgesic, antipyretic, antibiotic, antacid, tranquiliser.
  8. 8They act on bacterial structures.

Analgesics, antipyretics and antibiotics

From daily life

Paracetamol for a headache; antibiotics when a wound turns septic.

Simple definition

Analgesics relieve pain (narcotic: morphine; non-narcotic: aspirin, paracetamol). Antipyretics lower fever. Antibiotics kill or stop bacteria.

AspirinMaking aspirinsalicylic acidC₇H₆O₃M = 138+acetic anhydride(CH₃CO)₂OM = 102H⁺aspirinC₉H₈O₄M = 18013.8 g salicylic acid = 0.1 mol ⇒ 0.1 × 180 = 18 g aspirin (100 %)Actions: analgesic + antipyretic + blood-thinningParacetamol C₈H₉NO₂ (M = 151): gentler on the stomachMorphine comes from opium and can be addictive (narcotic)

In the figure : Preparation of aspirin.

Rule 1: Non-narcotic analgesics — Aspirin (acetylsalicylic acid) inhibits prostaglandin synthesis and thins blood (low dose in heart disease). Paracetamol is gentler on the stomach.

  • Easy : Salicylic acid + (CH₃CO)₂O ⇒ aspirin.
  • Medium : 13.8 g salicylic acid ⇒ 18 g aspirin (100 %).
  • Exam-type : Ibuprofen: anti-inflammatory.

Rule 2: Narcotic analgesics — Morphine and codeine (from opium) for severe pain; addictive and legally controlled.

  • Easy : Post-operative pain.
  • Medium : Codeine is also in cough syrups.
  • Exam-type : Heroin is a derivative (illegal).

Rule 3: Antibiotics — Penicillin (Fleming, 1928), bactericidal or bacteriostatic. Broad spectrum (tetracycline, chloramphenicol); narrow spectrum (penicillin G).

  • Easy : Chloramphenicol for typhoid.
  • Medium : Ofloxacin: a fluoroquinolone.
  • Exam-type : Some people are allergic to penicillin.

Calculation: aspirin from 13.8 g salicylic acid

  • Step 1: n = 13.8 ÷ 138 = 0.1 mol.
  • Step 2: 1 : 1 ⇒ aspirin = 0.1 mol.
  • Step 3: Mass = 0.1 × 180 = 18 g.

CET level (MCQ)

  • CET 1) A narcotic analgesic? 1) aspirin 2) paracetamol 3) morphine 4) ibuprofen — Answer: 3).
  • CET 2) Penicillin was discovered by? 1) Pasteur 2) Fleming 3) Koch 4) Lister — Answer: 2).

Real-life use: Pain/fever relief, low-dose aspirin as blood thinner, infection treatment.

Remember

Aspirin M = 180; paracetamol 151; morphine = narcotic; penicillin = Fleming.

Common mistake

Calling aspirin narcotic; it is non-narcotic.

CET trap

Antipyretic and analgesic differ, but aspirin is both.

Shortcut

Memory clue: "morphine = narcotic".

Spot the difference

DrugTypeNote
Aspirinnon-narcoticblood thinner
Morphinenarcoticopium
Penicillinantibiotic1928

Practice questions

Easy
  1. 1Two types of analgesics.
  2. 2How is aspirin made?
  3. 3Source of morphine?
Medium
  1. 4An example of a broad-spectrum antibiotic.
  2. 5Aspirin from 13.8 g salicylic acid?
  3. 6Why does aspirin thin blood?
Challenging
  1. 7Bactericidal versus bacteriostatic.
  2. 8How do you avoid resistance?
Show answers (try them yourself first)
  1. 1Narcotic and non-narcotic.
  2. 2Salicylic acid + acetic anhydride.
  3. 3Opium.
  4. 4Tetracycline.
  5. 518 g.
  6. 6It reduces platelet aggregation.
  7. 7Kills / halts growth.
  8. 8Complete the course on a doctor's advice.

Antacids, antihistamines and tranquilisers

From daily life

After spicy food a pinch of soda or milk of magnesia calms heartburn; that is an antacid.

Simple definition

Antacids neutralise excess stomach HCl (pH ≈ 1.5–2). Antihistamines block histamine receptors in allergy. Tranquilisers reduce anxiety and stress.

AntacidsAntacids: neutralising HClGastric juice pH ≈ 1.5 – 2 (HCl)too much acid ⇒ indigestion, heartburnMg(OH)₂ (milk of magnesia)Mg(OH)₂ + 2HCl → MgCl₂ + 2H₂O1 g ⇒ 0.0343 mol HClNaHCO₃NaHCO₃ + HCl → NaCl + H₂O + CO₂1 g ⇒ 0.0119 mol HClAl(OH)₃Al(OH)₃ + 3HCl → AlCl₃ + 3H₂Omay cause constipationRanitidine/cimetidine block H₂ receptors ⇒ less acid secretionPer gram, Mg(OH)₂ neutralises ≈ 2.9 × more acid

In the figure : Antacids and HCl neutralisation.

Rule 1: Antacids — NaHCO₃, Mg(OH)₂ and Al(OH)₃ act briefly; ranitidine and cimetidine block H₂ receptors and reduce secretion.

  • Easy : Mg(OH)₂ + 2HCl → MgCl₂ + 2H₂O.
  • Medium : 1 g Mg(OH)₂ ⇒ 0.0343 mol HCl; 1 g NaHCO₃ ⇒ 0.0119 mol.
  • Exam-type : NaHCO₃ gives CO₂ (belching) and can make the stomach alkaline.

Rule 2: Antihistamines — Histamine on H₁ receptors causes allergy (sneezing, itching). Brompheniramine and terfenadine block H₁ but not H₂, so they do not cut acid.

  • Easy : Cetirizine for pollen allergy.
  • Medium : Drowsiness is a side effect.
  • Exam-type : No effect on stomach acid.

Rule 3: Tranquilisers — Equanil, valium and barbiturates (seconal) help anxiety and sleep; antidepressants (iproniazid) treat depression. Never without medical advice.

  • Easy : Barbiturates are sleeping pills.
  • Medium : Dangerous with alcohol.
  • Exam-type : Habit-forming.

Calculation: acid neutralised by 1 g Mg(OH)₂ versus 1 g NaHCO₃

  • Step 1: Mg(OH)₂: 1 ÷ 58.3 = 0.01715 mol; 2 HCl ⇒ 0.0343 mol.
  • Step 2: NaHCO₃: 1 ÷ 84 = 0.0119 mol; 1 HCl ⇒ 0.0119 mol.
  • Step 3: Ratio 0.0343 ÷ 0.0119 ≈ 2.9.

CET level (MCQ)

  • CET 1) Acid in the stomach? 1) H₂SO₄ 2) HCl 3) HNO₃ 4) CH₃COOH — Answer: 2).
  • CET 2) Which blocks H₂ receptors as an antacid? 1) brompheniramine 2) ranitidine 3) valium 4) morphine — Answer: 2).

Real-life use: Indigestion, allergy, insomnia, anxiety — common health problems.

Remember

pH 1.5–2; Mg(OH)₂ ≈ 2.9 × NaHCO₃; H₁ allergy, H₂ acid.

Common mistake

Saying antihistamines reduce stomach acid.

CET trap

Too much NaHCO₃ can make the stomach alkaline and trigger rebound acid.

Shortcut

Memory clue: "H₁ = allergy, H₂ = acid".

Spot the difference

DrugTargetUse
RanitidineH₂less acid
BrompheniramineH₁allergy
Valiumbrainanxiety

Practice questions

Easy
  1. 1What is an antacid?
  2. 2Two antacid compounds.
  3. 3How does ranitidine work?
Medium
  1. 4Why use antihistamines?
  2. 5What are tranquilisers?
  3. 6HCl neutralised by 1 g Mg(OH)₂?
Challenging
  1. 7What are barbiturates?
  2. 8Why is excess NaHCO₃ risky?
Show answers (try them yourself first)
  1. 1A substance neutralising excess stomach acid.
  2. 2Mg(OH)₂, NaHCO₃.
  3. 3It blocks H₂ receptors.
  4. 4To stop allergic reactions.
  5. 5Drugs reducing anxiety and stress.
  6. 60.0343 mol.
  7. 7Sleeping/sedative drugs.
  8. 8It can make the stomach alkaline with rebound acid.

Antimicrobials and antifertility drugs

From daily life

Dettol or tincture of iodine on a wound, phenyl on the floor — both kill germs, but for different jobs.

Simple definition

Antimicrobials stop microbial growth. Antiseptics act on living tissue (mild); disinfectants act on non-living objects (strong). Antifertility drugs are hormonal (norethindrone + ethinylestradiol).

AntimicrobialsConcentrations of antimicrobialsPhenol 0.2 %antiseptic (on skin)Phenol 1 %disinfectant (on objects)Tincture of iodine 2–3 %wound antisepticBoric acidmild; for eyesCl₂ 0.2–0.4 ppmwater disinfectantSO₂disinfectant / preservativeAntiseptic = on living tissue; disinfectant = on non-living objects

In the figure : Use by concentration.

Rule 1: Antiseptics — Phenol 0.2 % is antiseptic, 1 % disinfectant; Dettol = chloroxylenol + terpineol; tincture of iodine 2–3 % (iodine in alcohol); boric acid for eyes.

  • Easy : 100 mL of 0.2 % phenol ⇒ 0.2 g phenol.
  • Medium : Iodoform on wounds.
  • Exam-type : Bithionol in medicated soaps.

Rule 2: Disinfectants — Cl₂ at 0.2–0.4 ppm for drinking water; SO₂ (preservative); 1 % phenol; bleaching powder.

  • Easy : For 1 m³ of water, 0.2–0.4 g Cl₂ (ppm = g/m³).
  • Medium : Chlorine in swimming pools.
  • Exam-type : Ozone also disinfects water.

Rule 3: Antifertility drugs — Norethindrone (progestogen) + ethinylestradiol (oestrogen) stop ovulation (pills).

  • Easy : Key ingredient norethindrone.
  • Medium : Only on medical advice.
  • Exam-type : Hormone-based.

Calculation: Cl₂ for 5 m³ water at 0.2 ppm

  • Step 1: 0.2 ppm = 0.2 g per m³.
  • Step 2: 5 m³ ⇒ 5 × 0.2 = 1.0 g.
  • Step 3: For 0.4 ppm, 2.0 g.

CET level (MCQ)

  • CET 1) Phenol 0.2 % is a? 1) disinfectant 2) antiseptic 3) antibiotic 4) tranquiliser — Answer: 2).
  • CET 2) Dettol contains? 1) phenol + iodine 2) chloroxylenol + terpineol 3) boric acid 4) KMnO₄ — Answer: 2).

Real-life use: Wound care, water purification, hygiene, family planning.

Remember

0.2 % phenol = antiseptic; 1 % = disinfectant; Cl₂ 0.2–0.4 ppm; norethindrone.

Common mistake

Treating antiseptic and disinfectant as the same.

CET trap

The use changes with phenol strength (0.2 % versus 1 %).

Shortcut

Memory clue: "living = antiseptic, non-living = disinfectant".

Spot the difference

ItemAntisepticDisinfectant
Applied toliving tissueobjects
Phenol0.2 %1 %

Practice questions

Easy
  1. 1Antiseptic versus disinfectant.
  2. 2Two phenol strengths and uses.
  3. 3Components of Dettol.
Medium
  1. 4What is tincture of iodine?
  2. 5Cl₂ ppm in water?
  3. 6Cl₂ for 5 m³ at 0.2 ppm?
Challenging
  1. 7Ingredients of birth-control pills.
  2. 8Phenol in 100 mL of 0.2 % solution?
Show answers (try them yourself first)
  1. 1Living tissue versus objects.
  2. 20.2 % antiseptic; 1 % disinfectant.
  3. 3Chloroxylenol + terpineol.
  4. 4Iodine in alcohol (2–3 %).
  5. 50.2–0.4 ppm.
  6. 61.0 g.
  7. 7Norethindrone + ethinylestradiol.
  8. 80.2 g.

Chemicals in food: preservatives, sweeteners, antioxidants

From daily life

Jam and pickles last for months because of preservatives (salt, sugar, sodium benzoate).

Simple definition

Preservatives stop microbial growth (sodium benzoate, sorbic acid). Artificial sweeteners are low-calorie (saccharin, aspartame). Antioxidants stop fat oxidation (BHT, BHA).

SweetnessRelative sweetness (sucrose = 1)sucrose1×aspartame100×saccharin550×sucralose600×alitame2000×(log scale)Same sweetness as 1 g sugar: saccharin 1.8 mg, aspartame 10 mgAspartame is unstable on cooking; sucralose is stable

In the figure : Sweetness comparison (log).

Rule 1: Preservatives — Salt, sugar, oil, vinegar (traditional); sodium benzoate, sorbic acid, potassium metabisulphite.

  • Easy : Salt and oil in pickles.
  • Medium : Sodium benzoate in soft drinks.
  • Exam-type : Drying: removing water.

Rule 2: Artificial sweeteners — Versus sucrose: aspartame 100×, saccharin 550×, sucralose 600×, alitame 2000×. For diabetics; aspartame breaks down on cooking; sucralose is stable.

  • Easy : Equal to 1 g sugar: saccharin 1/550 g = 1.8 mg.
  • Medium : Aspartame: 1/100 g = 10 mg.
  • Exam-type : Phenylketonuria patients avoid aspartame.

Rule 3: Antioxidants — BHT and BHA react with oxygen themselves, protecting oils from rancidity; vitamins C and E are natural antioxidants.

  • Easy : Rancidity is oxidation.
  • Medium : BHA in chip packets.
  • Exam-type : Lemon juice keeps cut apple from browning (vitamin C).

Calculation: saccharin matching the sweetness of 1 g sugar

  • Step 1: Saccharin is 550 times sweeter.
  • Step 2: Needed = 1 g ÷ 550 = 0.00182 g.
  • Step 3: = 1.82 mg.

CET level (MCQ)

  • CET 1) Sweetest? 1) sucrose 2) aspartame 3) saccharin 4) alitame — Answer: 4).
  • CET 2) An antioxidant? 1) BHT 2) saccharin 3) NaCl 4) sorbic acid — Answer: 1).

Real-life use: Sugar-free drinks, jams, pickles, packaged foods.

Remember

Sweetness: 100, 550, 600, 2000; aspartame unstable on heating; BHT/BHA = antioxidants.

Common mistake

Treating preservatives and antioxidants as the same.

CET trap

Saccharin has almost no calories but is not sugar.

Shortcut

Memory clue: "100-550-600-2000" (as-sa-su-al).

Spot the difference

SubstanceSweetness ×
aspartame100
saccharin550
sucralose600
alitame2000

Practice questions

Easy
  1. 1What is a preservative?
  2. 2Name two artificial sweeteners.
  3. 3Why is aspartame not used in cooking?
Medium
  1. 4How do antioxidants work?
  2. 5Saccharin matching 1 g sugar?
  3. 6Advantage of sucralose.
Challenging
  1. 7Name traditional preservatives.
  2. 8Why does oil turn rancid?
Show answers (try them yourself first)
  1. 1A substance stopping microbial growth.
  2. 2Saccharin, aspartame.
  3. 3It decomposes on heating.
  4. 4They react with oxygen first.
  5. 51.82 mg.
  6. 6Stable on heating.
  7. 7Salt, sugar, oil.
  8. 8Because of oxidation.

Soaps and detergents

From daily life

Soap or detergent washes clothes; soap barely lathers in hard well water.

Simple definition

Soap: fat/oil + NaOH ⇒ sodium salts of fatty acids (saponification). Detergents: synthetic surfactants (sulphates/sulphonates). Both form micelles that carry away grease.

SoapsSoaps and detergentsSaponification: fat + 3NaOH → 3 soap + glycerol(C₁₇H₃₅COO)₃C₃H₅ + 3NaOH → 3C₁₇H₃₅COONa + C₃H₅(OH)₃890 g tristearin ⇒ 918 g soap + 92 g glycerolItemSoapDetergentNatureRCOO⁻Na⁺R–SO₄⁻Na⁺ / R–SO₃⁻Hard waterscum formsworks wellMediumalkalineanyBiodegradableyeslinear chain: yesTypes: anionic (SLS), cationic (CTAB), non-ionic

In the figure : Saponification and soap versus detergent.

Rule 1: Saponification — (C₁₇H₃₅COO)₃C₃H₅ + 3NaOH → 3C₁₇H₃₅COONa + C₃H₅(OH)₃. Glycerol is the by-product. KOH gives soft soap.

  • Easy : 890 g tristearin ⇒ 918 g soap + 92 g glycerol.
  • Medium : 89 g ⇒ 91.8 g soap.
  • Exam-type : Coconut oil soap lathers well.

Rule 2: Soap versus detergent — In hard water soap precipitates with Ca²⁺/Mg²⁺ (scum); detergent Ca/Mg salts are soluble ⇒ works in hard water, even in acidic media.

  • Easy : 2C₁₇H₃₅COO⁻ + Ca²⁺ → (C₁₇H₃₅COO)₂Ca ↓.
  • Medium : Sodium lauryl sulphate (SLS) is a detergent.
  • Exam-type : Detergents in shampoos and toothpaste.

Rule 3: Types of detergents and biodegradability — Anionic (SLS), cationic (CTAB, germicidal), non-ionic (liquid detergents). Straight chains are biodegradable; branched are not ⇒ foam pollution.

  • Easy : Branched ABS ⇒ foam in rivers.
  • Medium : Linear LAS is biodegradable.
  • Exam-type : CTAB in conditioners.

Calculation: soap from 89 g tristearin

  • Step 1: M(tristearin) = 890 ⇒ 89 g = 0.1 mol.
  • Step 2: 1 mol gives 3 mol soap ⇒ 0.3 mol.
  • Step 3: M(C₁₇H₃₅COONa) = 306 ⇒ 0.3 × 306 = 91.8 g.

CET level (MCQ)

  • CET 1) By-product of saponification? 1) glycerol 2) ethanol 3) CO₂ 4) water — Answer: 1).
  • CET 2) Which works in hard water? 1) soap 2) detergent 3) neither 4) NaOH only — Answer: 2).

Real-life use: Laundry, shampoos, dishwashing.

Remember

Soap = fatty acid salt + glycerol; detergent works in hard water; straight chain is biodegradable.

Common mistake

Writing that a detergent is a soap; its structure differs (sulphate/sulphonate).

CET trap

Soap turns into inactive fatty acid in acid; detergents do not.

Shortcut

Memory clue: "soap = scum, detergent = dissolves".

Spot the difference

ItemSoapDetergent
Hard waterscumworks
Acidic mediumnoworks
Biodegradableyesdepends on chain

Practice questions

Easy
  1. 1What is saponification?
  2. 2Why does soap fail in hard water?
  3. 3Three types of detergents.
Medium
  1. 4Soap from 89 g tristearin?
  2. 5Which detergent is biodegradable?
  3. 6How is soft soap made?
Challenging
  1. 7Expand SLS.
  2. 8Use of CTAB?
Show answers (try them yourself first)
  1. 1Fat + NaOH ⇒ soap + glycerol.
  2. 2Ca²⁺/Mg²⁺ precipitate.
  3. 3Anionic, cationic, non-ionic.
  4. 491.8 g.
  5. 5The straight-chain one.
  6. 6Using KOH.
  7. 7Sodium lauryl sulphate.
  8. 8Germicide and conditioners.

Safe use of chemicals in daily life

From daily life

Cleaning chemicals can be dangerous when mixed; reading every label matters.

Simple definition

Chemicals bring benefits and risks; proper dose, storage, mixing rules and environmental care are essential.

Rule 1: Household hazards — Bleach (NaOCl) + acid (toilet cleaner) ⇒ toxic Cl₂; bleach + ammonia ⇒ chloramines.

  • Easy : NaOCl + 2HCl → NaCl + Cl₂ + H₂O.
  • Medium : Never mix two cleaners.
  • Exam-type : Read the warnings on labels.

Rule 2: Safe use of medicines — Correct dose, expiry, medical advice; keep away from children; no expired medicines; finish antibiotic courses.

  • Easy : Do not exceed the paracetamol dose.
  • Medium : No tranquilisers without a doctor.
  • Exam-type : Recheck expiry dates regularly.

Rule 3: Environment — Branched detergents cause foam; plastic waste; water pollution; prefer biodegradable alternatives.

  • Easy : Use linear LAS.
  • Medium : Recycle plastics.
  • Exam-type : Treat wastewater.

Why are bleach + acid dangerous?

  • Step 1: NaOCl reacts with acid to give HOCl.
  • Step 2: HOCl + HCl → Cl₂ + H₂O.
  • Step 3: Cl₂ gas is harmful to breathe.

CET level (MCQ)

  • CET 1) Bleach + acid gives? 1) O₂ 2) Cl₂ 3) CO₂ 4) H₂ — Answer: 2).
  • CET 2) Biodegradable detergent? 1) branched 2) linear 3) both 4) none — Answer: 2).

Real-life use: Home cleaning, medicine safety, environmental care.

Remember

Bleach + acid = Cl₂; linear detergents; medicine dose and expiry.

Common mistake

The misconception that natural means safe.

CET trap

Mixing two different chemical cleaners.

Shortcut

Memory clue: "read the label, never mix".

Spot the difference

UnsafeSafe
mixing cleanersone at a time
expired drugscheck expiry

Practice questions

Easy
  1. 1Why are bleach + acid dangerous?
  2. 2Two medicine safety rules.
  3. 3Drawback of branched detergents.
Medium
  1. 4Why complete an antibiotic course?
  2. 5NaOCl + HCl equation.
  3. 6How would you cut plastic waste?
Challenging
  1. 7Name two household hazards.
  2. 8What is LAS?
Show answers (try them yourself first)
  1. 1Toxic Cl₂ forms.
  2. 2Check dose and expiry.
  3. 3Not biodegradable; foam.
  4. 4To avoid resistance.
  5. 5NaOCl + 2HCl → NaCl + Cl₂ + H₂O.
  6. 6Recycle and use alternatives.
  7. 7Bleach + acid; medicines within a child's reach.
  8. 8Linear alkylbenzene sulphonate.

Quick revision of the whole lesson

ConceptKey formula / fact
Drugenzyme/receptor target
AspirinM = 180
AntacidpH 1.5–2; Mg(OH)₂
Antisepticphenol 0.2 % / 1 %
Sweeteners100 / 550 / 600 / 2000
Soapfatty acid salt + glycerol
Detergentworks in hard water
Safetybleach + acid = Cl₂
Live figure

🚀 Quick revision of the whole lesson

In the app you can move this figure with your finger.

Open in the app

🎯 Most important points for the exam

  • Drugs and targets.
  • Analgesics and antibiotics.
  • Antacids, antihistamines, tranquilisers.
  • Antimicrobials and antifertility.
  • Food chemicals.
  • Soaps and detergents.
  • Safe use of chemicals.
Study mantra

understand the idea → remember the formula → solve the example → solve problems yourself.