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🇵🇰 COMSATS NTS-based Test · flashcards
COMSATS NTS-based Test Chemistry (NAT-IE / NAT-IM) Flashcards
52 question-and-answer cards covering Chemistry (NAT-IE / NAT-IM) as it is examined in COMSATS NTS-based Test. 24 of them are printed below, taken from across the deck — no signup, no paywall on the preview.
24 sample cards from the Chemistry (NAT-IE / NAT-IM) deck
Sampled from the end of the deck, so these are different cards from the ones shown on the syllabus page.
Does a catalyst change the position of equilibrium or the value of Kc?
No. A catalyst speeds up forward and reverse reactions equally, reaching equilibrium faster without changing its position or Kc.
Define enthalpy change (delta H) and distinguish exothermic from endothermic reactions.
delta H is the heat change at constant pressure. Exothermic: heat released, delta H is negative. Endothermic: heat absorbed, delta H is positive.
State Hess's law.
The total enthalpy change of a reaction is independent of the route taken, depending only on the initial and final states (since enthalpy is a state function).
Define standard enthalpy of formation (delta Hf).
The enthalpy change when one mole of a compound is formed from its elements in their standard states under standard conditions (298 K, 1 atm). For elements it is zero.
Define enthalpy of combustion.
The enthalpy change when one mole of a substance is completely burned in excess oxygen under standard conditions; always exothermic (negative).
Write the calorimetry equation used to calculate heat absorbed or released.
q = m c delta T, where m = mass, c = specific heat capacity, delta T = temperature change.
What are the periods and groups in the periodic table, and what does each correspond to?
Periods are horizontal rows (same number of electron shells); groups are vertical columns (same number of valence electrons / similar chemical properties).
Describe the trend in atomic radius across a period and down a group, with reasons.
Across a period it decreases (increasing nuclear charge pulls electrons closer); down a group it increases (more shells added).
Describe the trend in ionization energy across a period and down a group.
Ionization energy increases across a period (greater nuclear charge, smaller size) and decreases down a group (electrons farther from nucleus, more shielding).
How does metallic vs non-metallic character vary across a period and down a group?
Metallic character decreases across a period and increases down a group; non-metallic character does the opposite.
What is the general trend in electron affinity across a period?
Electron affinity generally becomes more negative (more energy released) across a period as atoms more readily gain electrons, with halogens having the highest values.
Name the s-block, p-block, d-block, and f-block in terms of the subshell being filled.
s-block = outermost s subshell filling (Groups 1-2); p-block = p subshell (Groups 13-18); d-block = d subshell (transition metals); f-block = f subshell (lanthanides/actinides).
Why are Group 1 elements called alkali metals and how does their reactivity change down the group?
They react with water to form alkaline (basic) hydroxides. Reactivity increases down the group as ionization energy decreases and the outer electron is more easily lost.
What is the general trend in reactivity of Group 17 (halogens) down the group, and why?
Reactivity decreases down the group because atomic size increases and the ability to attract/gain an electron (electronegativity) decreases.
List three characteristic properties of transition elements.
They form colored ions/compounds, show variable oxidation states, act as catalysts, and form complex ions (paramagnetic due to unpaired d electrons).
Why do transition metals exhibit variable oxidation states?
Because the energies of the 3d and 4s electrons are very close, allowing a variable number of electrons from both to participate in bonding.
Why are transition metal complexes often colored?
d-orbitals split into different energy levels in a ligand field; electrons absorb specific wavelengths of visible light during d-d transitions, and the complementary color is seen.
Define a homologous series and give its key features.
A family of organic compounds with the same general formula, similar chemical properties, and a gradation in physical properties, with each member differing from the next by a CH2 unit.
Compare the general reactivity of alkanes, alkenes, and alkynes.
Alkanes are saturated and relatively unreactive (undergo substitution); alkenes and alkynes are unsaturated and more reactive, undergoing addition reactions at their double/triple bonds.
What is the difference between substitution and addition reactions?
In substitution, an atom or group replaces another in a (usually saturated) molecule; in addition, atoms add across a double or triple bond, converting unsaturated to saturated.
Identify the functional group and a characteristic suffix for alcohols, aldehydes, ketones, and carboxylic acids.
Alcohol = -OH (-ol); aldehyde = -CHO (-al); ketone = C=O between carbons (-one); carboxylic acid = -COOH (-oic acid).
Distinguish electrophiles from nucleophiles.
Electrophiles are electron-pair acceptors (electron-deficient, e.g. H+, NO2+); nucleophiles are electron-pair donors (electron-rich, e.g. OH-, NH3, CN-).
Define the mole and Avogadro's number.
A mole is the amount of substance containing as many particles as there are atoms in 12 g of carbon-12; Avogadro's number = 6.022 x 10^23 particles per mole.
Write the formulas relating moles to mass, to number of particles, and to gas volume at STP.
moles = mass / molar mass; moles = number of particles / 6.022 x 10^23; moles of gas at STP = volume / 22.4 L.
What this deck covers
The Chemistry (NAT-IE / NAT-IM) deck follows the COMSATS NTS-based Test Chemistry (NAT-IE / NAT-IM) syllabus — 4 chapters and 14 topics — so questions land on material that is genuinely examinable rather than trivia around it. That works out to roughly 13.0 cards per chapter.
Answers are written to be recallable, not just readable — averaging about 150 characters, which is long enough to carry the reasoning and short enough to say out loud.
A deck like this earns its keep on the second and third pass. Read the syllabus first so you know the shape of the subject, then use the cards to find the specific facts that have not stuck.
Chemistry (NAT-IE / NAT-IM) flashcards FAQ
How many Chemistry (NAT-IE / NAT-IM) flashcards are in this COMSATS NTS-based Test deck?
52 cards. This page previews 24 of them, sampled evenly across the deck so you can judge the difficulty before installing anything.
Are these COMSATS NTS-based Test flashcards free?
Yes. The preview here is free to read with no signup, and the full 52-card deck is free inside the Examius app.
What do the Chemistry (NAT-IE / NAT-IM) cards cover?
They follow the COMSATS NTS-based Test Chemistry (NAT-IE / NAT-IM) syllabus — 4 chapters and 14 topics — so the questions track what is actually examinable.
How should I use these flashcards?
Read the syllabus first so you know the shape of the subject, then drill the deck. Examius schedules each card with spaced repetition, so cards you keep missing come back sooner and ones you know drift further apart.