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HEC USAT Chemistry Syllabus
The Chemistry syllabus for HEC USAT in full: 6 chapters and 19 topics, every one listed below, plus 50 Chemistry flashcards with answers.
Chemistry syllabus: all 6 chapters
Expand any chapter to see its topics and sub-topics.
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Atomic Structure
3 topics- Subatomic Particles
- Electronic Configuration
- Periodic Table and Periodicity
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Chemical Bonding
3 topics- Ionic and Covalent Bonds
- Molecular Geometry
- Intermolecular Forces
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States of Matter
3 topics- Gas Laws
- Liquids and Solids
- Phase Changes
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Physical Chemistry
4 topics- Stoichiometry
- Chemical Equilibrium
- Thermochemistry
- Reaction Kinetics
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Solutions and Acids and Bases
3 topics- Concentration Units
- pH and Buffers
- Electrochemistry
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Organic Chemistry
3 topics- Hydrocarbons
- Functional Groups
- Alcohols, Aldehydes and Acids
HEC USAT Chemistry flashcards — 50 questions with answers
What are the three main subatomic particles, and what is the relative charge of each?
Proton (+1), neutron (0), and electron (−1).
Where in the atom is nearly all the mass concentrated, and which particles contribute to it?
In the nucleus, contributed by protons and neutrons (the electron mass is negligible).
What does the atomic number (Z) of an element represent?
The number of protons in the nucleus (and the number of electrons in a neutral atom).
What is the mass number (A) of an atom?
The total number of protons plus neutrons in the nucleus (A = Z + number of neutrons).
What are isotopes?
Atoms of the same element with the same number of protons but different numbers of neutrons (same Z, different mass number).
State the maximum number of electrons a shell can hold in terms of its principal quantum number n.
2n² electrons (e.g., n=1 holds 2, n=2 holds 8, n=3 holds 18).
What is the Aufbau principle?
Electrons fill atomic orbitals in order of increasing energy, lowest-energy orbitals first.
State the Pauli exclusion principle.
No two electrons in an atom can have the same set of four quantum numbers; an orbital holds at most two electrons with opposite spins.
State Hund's rule of maximum multiplicity.
Electrons occupy degenerate (equal-energy) orbitals singly with parallel spins before pairing up.
How many electrons can s, p, d, and f subshells hold respectively?
s = 2, p = 6, d = 10, f = 14 electrons.
Write the ground-state electronic configuration of a neutral chlorine atom (Z = 17).
1s² 2s² 2p⁶ 3s² 3p⁵.
What is the order of orbital filling for the first few orbitals according to the (n+l) rule?
1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p...
In the periodic table, what does a period (horizontal row) correspond to?
The highest principal quantum number (n) / outermost occupied shell of the elements in that row.
What does a group (vertical column) of the periodic table indicate about its elements?
Elements have the same number of valence electrons and therefore similar chemical properties.
Name the four main blocks of the periodic table.
The s-block, p-block, d-block (transition metals), and f-block (lanthanides and actinides).
How does atomic radius generally change across a period (left to right) and down a group?
It decreases across a period and increases down a group.
Define ionization energy.
The energy required to remove the most loosely bound (outermost) electron from a gaseous atom or ion.
How does first ionization energy generally trend across a period and down a group?
It increases across a period and decreases down a group.
Define electronegativity and name the most electronegative element.
The tendency of an atom to attract a shared pair of electrons in a bond; fluorine is the most electronegative.
How does electron affinity generally trend across a period?
It generally becomes more negative (energy released increases) across a period from left to right.
Show the other 30 Chemistry flashcards
What is an ionic bond and how does it form?
An electrostatic attraction between oppositely charged ions, formed by the transfer of electrons from a metal to a non-metal.
What is a covalent bond?
A bond formed by the sharing of one or more pairs of electrons between two atoms (typically non-metals).
Distinguish between a polar and a nonpolar covalent bond.
A polar covalent bond has unequal electron sharing (electronegativity difference); a nonpolar covalent bond has equal sharing (zero or very small electronegativity difference).
What is the octet rule?
Atoms tend to gain, lose, or share electrons to achieve a full outer shell of eight electrons (a stable noble-gas configuration).
What is a coordinate (dative) covalent bond?
A covalent bond in which both shared electrons are donated by the same atom.
According to VSEPR theory, what determines the shape of a molecule?
Electron pairs (bonding and lone pairs) around the central atom repel each other and arrange to minimize repulsion.
What is the molecular geometry and bond angle of a molecule with four bonding pairs and no lone pairs (e.g., CH₄)?
Tetrahedral, with bond angles of about 109.5°.
What is the shape and bond angle of water (H₂O), which has two bonding pairs and two lone pairs?
Bent (angular), with a bond angle of about 104.5°.
What is the molecular shape and bond angle of ammonia (NH₃)?
Trigonal pyramidal, with a bond angle of about 107°.
What is the molecular geometry of a molecule with three bonding pairs and no lone pairs (e.g., BF₃)?
Trigonal planar, with bond angles of 120°.
List the three main types of intermolecular forces from weakest to strongest.
London dispersion forces, dipole–dipole forces, and hydrogen bonding.
What conditions are required for hydrogen bonding to occur?
Hydrogen must be bonded directly to a highly electronegative atom (N, O, or F) and interact with a lone pair on another N, O, or F.
What are London dispersion forces and what increases their strength?
Weak attractions from temporary instantaneous dipoles; their strength increases with the number of electrons (larger molar mass / surface area).
State Boyle's law.
At constant temperature and amount of gas, the volume of a gas is inversely proportional to its pressure (PV = constant).
State Charles's law.
At constant pressure, the volume of a gas is directly proportional to its absolute (Kelvin) temperature (V/T = constant).
Write the ideal gas equation and identify each term.
PV = nRT, where P = pressure, V = volume, n = moles, R = gas constant, T = absolute temperature.
State Avogadro's law.
At the same temperature and pressure, equal volumes of all gases contain equal numbers of molecules (V ∝ n).
State Dalton's law of partial pressures.
The total pressure of a mixture of non-reacting gases equals the sum of the partial pressures of the individual gases.
What molar volume does one mole of an ideal gas occupy at STP?
22.4 litres at standard temperature and pressure (0 °C, 1 atm).
What is surface tension in a liquid and what causes it?
The tendency of a liquid surface to minimize its area, caused by unbalanced intermolecular attractive forces at the surface.
What is the difference between crystalline and amorphous solids?
Crystalline solids have a regular, repeating long-range ordered arrangement of particles; amorphous solids lack long-range order.
Define vapor pressure of a liquid.
The pressure exerted by a vapor in equilibrium with its liquid at a given temperature.
At what point does a liquid boil in terms of vapor pressure?
When its vapor pressure equals the external (atmospheric) pressure.
Name the phase change from solid directly to gas, and the reverse change.
Sublimation (solid to gas) and deposition (gas to solid).
Name the phase changes: solid to liquid, liquid to gas, and gas to liquid.
Melting (fusion), vaporization (evaporation/boiling), and condensation respectively.
What is a mole and how many particles does it contain (Avogadro's number)?
The amount of substance containing 6.022 × 10²³ particles (atoms, molecules, or ions).
How do you calculate the number of moles from a given mass of a substance?
Moles = mass (g) ÷ molar mass (g/mol).
What is a limiting reagent in a chemical reaction?
The reactant that is completely consumed first, limiting the amount of product formed.
State Le Chatelier's principle.
If a system at equilibrium is disturbed by a change in concentration, pressure, or temperature, the equilibrium shifts to counteract the change.
What does a negative enthalpy change (ΔH < 0) indicate about a reaction?
The reaction is exothermic, releasing heat to the surroundings.
HEC USAT Chemistry FAQ
What is in the HEC USAT Chemistry syllabus?
HEC USAT Chemistry is split into 6 chapters: Atomic Structure, Chemical Bonding, States of Matter, Physical Chemistry, Solutions and Acids and Bases and Organic Chemistry. Together they contain 19 topics.
How many chapters are in HEC USAT Chemistry?
6 chapters, containing 19 topics. The largest chapter is Physical Chemistry, with 4 topics.
Are there flashcards for HEC USAT Chemistry?
Yes — a 50-card Chemistry deck, printed in full in the flashcards section of this page and available in the Examius app with spaced repetition. The free plan covers one exam of your choice, including its flashcards; Examius Pro, a one-time purchase, unlocks every other exam and deck.