Most Repeated MDCAT Chemistry MCQs — Past Papers with Answers

What MDCAT Chemistry repeats

Acids–bases–salts, organic basics, hydrocarbons and carbonyl tests come most often. There is no C9 in this most-repeated set — so do not hunt for a missing chapter number. Rare MCQs do have C9 solutions.

Numericals use simple constants you already know: $C=12,O=16,NA=6.022\times 10^{23}.$ Empirical formula is moles, not mass percent copied as a formula.

MDCAT Chemistry past-paper chapter list

Nineteen chapters. C1–C8, then C10–C20. Each line is a quiz.

• C1 · Fundamental Concepts — 9 most-repeated MCQs. Often asked: Mole, Molar mass, Empirical formula, Molecular formula.
• C2 · Atomic Structure — 14 most-repeated MCQs. Often asked: Bohr radius idea, 2n², Quantum n, Quantum l.
• C3 · Gases — 8 most-repeated MCQs. Often asked: Boyle, Charles, Ideal gas, Graham.
• C4 · Liquids and Solids — 9 most-repeated MCQs. Often asked: H-bond requirement, Water BP anomaly, Vapour pressure, Ionic vs molecular solid.
• C5 · Chemical Energetics — 12 most-repeated MCQs. Often asked: Exothermic $\Delta H$, Hess law, $\Delta H$ f, Bond energy.
• C6 · Chemical Equilibrium — 8 most-repeated MCQs. Often asked: Kc writing, Solids omitted, Le Chatelier P, Le Chatelier T exo.
• C7 · Electrochemistry — 9 most-repeated MCQs. Often asked: Oxidation definition, Anode, Galvanic signs, SHE.
• C8 · Chemical Kinetics — 8 most-repeated MCQs. Often asked: Rate definition, First order unit, Second order unit, Ea / Arrhenius.
• C10 · Acids Bases Salts — 21 most-repeated MCQs · 2 short quizzes. Often asked: pH def, pOH, Strong vs weak, Bronsted.
• C11 · s- and p-block — 6 most-repeated MCQs. Often asked: Alkali metals, Halogens, Noble gases, Ionization trend.
• C12 · Transition Elements — 6 most-repeated MCQs. Often asked: Variable OS, Colour, Catalysis, Complex ion.
• C13 · Organic fundamentals / bonding — 22 most-repeated MCQs · 2 short quizzes. Often asked: Ionic vs covalent, VSEPR AX4, VSEPR AX3, VSEPR AX2.
• C14 · Hydrocarbons — 16 most-repeated MCQs. Often asked: Free radical halogenation, Alkene addition, Markovnikov, Anti-Markovnikov.
• C15 · Alkyl Halides — 4 most-repeated MCQs. Often asked: SN2 traits, SN1 traits, $E_2$, Grignard.
• C16 · Alcohols and Phenols — 11 most-repeated MCQs. Often asked: Classification 1 2 3, Oxidation $2^{\circ }$, Oxidation $1^{\circ }$, Lucas.
• C17 · Aldehydes and Ketones — 13 most-repeated MCQs. Often asked: Tollens, Fehling, Nucleophilic addition, Aldol.
• C18 · Carboxylic Acids — 5 most-repeated MCQs. Often asked: Acidity order, Esterification, Soap, Decarboxylation idea.
• C19 · Amino Acids and Proteins — 5 most-repeated MCQs. Often asked: Zwitterion, Peptide in chem, Isoelectric, Peptide.
• C20 · Macromolecules — 4 most-repeated MCQs. Often asked: Addition polymer, Condensation polymer, Acid rain memory, Greenhouse memory.

How to practise Chemistry without getting lost

1. C1 moles and C10 pH first. They help everything else.
2. C6 equilibrium and C8 kinetics as a pair — K does not move with a catalyst.
3. Organic in order: basics → hydrocarbons → alkyl halides → alcohols → carbonyls → acids.
4. Lock, read the why, retry. The mix-up is almost always the neighbouring test (Fehling for a ketone, SN1 for a methyl).