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NUST Entry Test (NET) Complete Guide 2025
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NUST Entry Test (NET)
Complete Study Guide

Comprehensive, exam-focused notes covering all five NET sections — Mathematics, Physics, Chemistry, English, and Intelligence. Master every concept tested at NUST with formulas, worked examples, and exam strategy.

16
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5
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200+
Formulas
100+
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NET 2025 Format: 200 MCQs in 3 hours (180 min). Mathematics 80 Qs, Physics 60 Qs, Chemistry 40 Qs, English 10 Qs, Intelligence 10 Qs. Each correct answer = +1 mark. No negative marking. Score is merit-based for B.Eng admissions across NUST campuses.
Mathematics — 80 Questions (40%)
HIGH
🔢
Math · M1
Algebra & Number Systems
Quadratics, logs, sequences, binomial, partial fractions
Study now →
HIGH
Math · M2
Functions, Limits & Continuity
Domain/range, limit laws, L'Hôpital, continuity
Study now →
HIGH
d/dx
Math · M3
Differentiation & Applications
All rules, maxima/minima, curve sketching, rates
Study now →
HIGH
Math · M4
Integration
Indefinite, definite, techniques, area under curve
Study now →
MED
📐
Math · M5
Trigonometry
All ratios, identities, inverse trig, equations
Study now →
MED
📏
Math · M6
Coordinate Geometry
Lines, circles, conics, distance, tangents
Study now →
MED
Math · M7
Matrices, Vectors & Probability
Matrix ops, dot/cross products, probability rules
Study now →
Physics — 60 Questions (30%)
HIGH
🚀
Physics · P1
Mechanics
Kinematics, Newton's laws, work-energy, momentum, rotation
Study now →
HIGH
🌊
Physics · P2
Waves, Heat & Thermodynamics
SHM, wave equations, gas laws, thermodynamics laws
Study now →
HIGH
Physics · P3
Electricity & Magnetism
Coulomb, circuits, capacitors, magnetic force, induction
Study now →
MED
🔬
Physics · P4
Optics & Modern Physics
Reflection, refraction, interference, photoelectric, nuclear
Study now →
Chemistry — 40 Questions (20%)
HIGH
⚗️
Chemistry · C1
Physical Chemistry
Atomic structure, bonding, thermodynamics, equilibrium, kinetics
Study now →
MED
🧪
Chemistry · C2
Inorganic Chemistry
Periodic table, s/p/d-block, acids/bases, electrochemistry
Study now →
MED
🔗
Chemistry · C3
Organic Chemistry
Hydrocarbons, functional groups, reactions, isomerism
Study now →
English & Intelligence — 10+10 Questions (10%)
LOW
📝
English · E1
Grammar, Vocabulary & Writing
Sentence correction, synonyms, antonyms, comprehension
Study now →
LOW
🧠
Intelligence · I1
Analytical Reasoning & IQ
Number series, spatial, logical deduction, analogies
Study now →

NET 2025 — Full Structure at a Glance

📐 Mathematics80 Qs · 40%
⚡ Physics60 Qs · 30%
⚗️ Chemistry40 Qs · 20%
📝 English10 Qs · 5%
🧠 Intelligence10 Qs · 5%
⏱ Total Time200 Qs · 3 Hours

1. Merit Formula

NUST calculates aggregate merit for admission as follows:

Aggregate Formula
Merit = (NET Score × 50%) + (FSc/A-Level × 25%) + (Matric/O-Level × 15%) + (HAT/Interview × 10%)
Note: Exact weights may vary slightly by department. Verify from NUST's official prospectus.

2. Exam Strategy

1
Prioritize Mathematics (40%)
Math carries the most weight. Aim for 70+/80 correct. Strong calculus (differentiation + integration) alone gives you ~20 marks.
2
Secure Physics (30%)
Mechanics and Electromagnetism are highest-yield. Know formulas cold — most Physics MCQs are formula-plugging with one conceptual twist.
3
Attempt All Questions (No Negative Marking!)
NET 2025 has no negative marking. Never leave a blank. If stuck, eliminate 2 options and guess from remaining 2 — statistically gives +0.5 marks.
4
Time Allocation
Math: ~60 min | Physics: ~50 min | Chemistry: ~30 min | English: ~8 min | Intelligence: ~8 min | Review: 24 min. Stick to this allocation.
5
Don't Over-invest in English & Intelligence
Together they are only 10%. Spend 3–4 days max on them. Use freed time to strengthen Math and Physics.

3. Key Subject-wise Tips

📐 Mathematics Tips
Learn all differentiation and integration formulas. Practice quadratic/cubic equations. Know Binomial theorem general term. Series (AP/GP) formulas are frequently tested.
⚡ Physics Tips
Memorize all unit conversions. Draw free body diagrams for mechanics. For EM problems, identify the law (Coulomb, Faraday, Lenz) first, then apply formula.
⚗️ Chemistry Tips
Focus on physical chemistry (equilibrium, kinetics, electrochemistry). Organic reaction mechanisms are frequently tested. Know periodic trends cold.
🧠 Intelligence Tips
For number series: find differences, ratios, or squares. For analogies: identify the relationship type (part-whole, category, function) first before picking answer.
💡 NET Focus
Quadratic equations, logarithms, sequences, binomial theorem and partial fractions together account for ~15–18 marks. Master all formulas and standard techniques cold.

1. Quadratic Equations

Quadratic Formula
x = (−b ± √(b²−4ac)) / 2a
Discriminant (Δ)
Δ = b²−4ac
Δ>0: 2 real roots; Δ=0: equal; Δ<0: complex
Vieta's Formulas
Sum of roots = −b/a
Product of roots = c/a
Sum of Squares
α²+β² = (α+β)²−2αβ
Sum of Cubes
α³+β³ = (α+β)³−3αβ(α+β)
New Equation (roots ×k)
Replace x with x/k in original equation

2. Laws of Logarithms

Product Rule
log_a(xy) = log_a x + log_a y
Quotient Rule
log_a(x/y) = log_a x − log_a y
Power Rule
log_a(xⁿ) = n·log_a x
Change of Base
log_a x = log x / log a = ln x / ln a
Special Values
log_a a=1; log_a 1=0; log_a(aⁿ)=n
Reciprocal
log_a b = 1 / log_b a

3. Sequences & Series

Typenth TermSum of n termsKey Condition
Arithmetic (AP)aₙ = a + (n−1)dSₙ = n/2 [2a + (n−1)d]Common difference d constant
Geometric (GP)aₙ = arⁿ⁻¹Sₙ = a(1−rⁿ)/(1−r), r≠1Common ratio r constant
GP (Infinite, |r|<1)S∞ = a / (1−r)Converges only if |r| < 1
Harmonic (HP)1/aₙ is APNo simple closed formReciprocals form AP
Sum of natural numbersΣn = n(n+1)/2
Sum of squaresΣn² = n(n+1)(2n+1)/6
Sum of cubesΣn³ = [n(n+1)/2]²

4. Binomial Theorem

General Term
(a + b)ⁿ → Tᵣ₊₁ = ⁿCᵣ · aⁿ⁻ʳ · bʳ
Middle term: if n is even → T_(n/2 +1); if n is odd → T_((n+1)/2) and T_((n+3)/2)
Expansion
(a+b)ⁿ = Σ ⁿCᵣ aⁿ⁻ʳ bʳ (r = 0 to n)
nCr Formula
ⁿCᵣ = n! / [r!(n−r)!]
Pascal's Triangle Row n
Coefficients: ⁿC₀, ⁿC₁, … ⁿCₙ
Worked Example
Find the term independent of x in the expansion of (x − 1/x²)⁹
General term: T_(r+1) = ⁹Cᵣ · x^(9−r) · (−1/x²)^r = ⁹Cᵣ · (−1)^r · x^(9−r−2r)
For term independent of x: 9 − 3r = 0 → r = 3
T₄ = ⁹C₃ · (−1)³ = 84 × (−1) = −84
Answer: −84

5. Partial Fractions (4 Cases)

Denominator TypeFormExample
Non-repeated linearA/(x−a) + B/(x−b)(3x+1)/[(x−1)(x+2)]
Repeated linearA/(x−a) + B/(x−a)²5/[(x+1)(x+1)²]
Irreducible quadraticA/(x−a) + (Bx+C)/(x²+bx+c)(x+2)/[(x−1)(x²+4)]
Improper fractionDo polynomial long division first(x³+1)/(x²−1)
💡 NET Focus
Limits (especially L'Hôpital's rule and standard forms) are heavily tested. Continuity conditions appear as MCQs. Know domain/range rules cold.

1. Standard Limit Results

Polynomial Limit
lim(x→a) f(x) = f(a) [direct sub]
0/0 Form — L'Hôpital
lim f/g = lim f'/g' (if 0/0 or ∞/∞)
sin x / x
lim(x→0) sin x / x = 1
tan x / x
lim(x→0) tan x / x = 1
eˣ − 1 / x
lim(x→0) (eˣ−1)/x = 1
ln(1+x) / x
lim(x→0) ln(1+x)/x = 1
Compound Interest Form
lim(n→∞) (1 + 1/n)ⁿ = e
aⁿ−bⁿ / (a−b) limit
lim(x→a) (xⁿ−aⁿ)/(x−a) = naⁿ⁻¹

2. Continuity & Differentiability

3 Conditions for Continuity at x = a
1. f(a) is defined   2. lim(x→a) f(x) exists   3. lim = f(a)
All three must hold. If any fails, f is discontinuous at x = a.
⚠️ Common Mistake
A function can be continuous but NOT differentiable (e.g., f(x)=|x| at x=0). But differentiability always implies continuity.

3. Domain Rules

ExpressionDomain Restriction
√f(x)f(x) ≥ 0
1/f(x)f(x) ≠ 0
log f(x)f(x) > 0
sin⁻¹(f(x))−1 ≤ f(x) ≤ 1
PolynomialAll real numbers ℝ
💡 NET Focus
Differentiation rules (especially chain rule, product/quotient rules) and maxima/minima problems are NET favorites. Expect 10–14 marks from this topic.

1. Differentiation Rules

Power Rule
d/dx(xⁿ) = nxⁿ⁻¹
Product Rule
d/dx(uv) = u'v + uv'
Quotient Rule
d/dx(u/v) = (u'v − uv') / v²
Chain Rule
d/dx[f(g(x))] = f'(g(x)) · g'(x)
d/dx(eˣ)
d/dx(aˣ)
aˣ · ln a
d/dx(ln x)
1/x
d/dx(log_a x)
1 / (x · ln a)

2. Trig & Inverse Trig Derivatives

FunctionDerivativeFunctionDerivative
sin xcos xsin⁻¹ x1/√(1−x²)
cos x−sin xcos⁻¹ x−1/√(1−x²)
tan xsec² xtan⁻¹ x1/(1+x²)
cot x−cosec² xcot⁻¹ x−1/(1+x²)
sec xsec x tan xsec⁻¹ x1/(x√(x²−1))
cosec x−cosec x cot xcosec⁻¹ x−1/(x√(x²−1))

3. Applications: Maxima & Minima

1
Find f'(x) and set f'(x) = 0
Solve for critical points (where slope is zero)
2
Apply Second Derivative Test
f''(x) < 0 → local maximum; f''(x) > 0 → local minimum; f''(x) = 0 → inconclusive (use first derivative test)
3
Check endpoints for absolute extrema
On a closed interval [a,b], evaluate f at all critical points AND at a and b
Worked Example — Maxima/Minima
Find the maximum and minimum values of f(x) = 2x³ − 9x² + 12x − 4
f'(x) = 6x² − 18x + 12 = 6(x² − 3x + 2) = 6(x−1)(x−2) = 0 → x = 1, 2
f''(x) = 12x − 18
At x=1: f''(1) = −6 < 0 → Local maximum. f(1) = 2−9+12−4 = 1
At x=2: f''(2) = 6 > 0 → Local minimum. f(2) = 16−36+24−4 = 0
Local Max = 1 at x=1 | Local Min = 0 at x=2
💡 NET Focus
Expect 8–12 integration questions. Know standard integrals, substitution, by-parts, and definite integral evaluation. Area between curves appears frequently.

1. Standard Integrals

Power Rule
∫xⁿ dx = xⁿ⁺¹/(n+1) + C (n≠−1)
1/x
∫(1/x) dx = ln|x| + C
∫eˣ dx = eˣ + C
∫aˣ dx = aˣ/ln a + C
sin x
∫sin x dx = −cos x + C
cos x
∫cos x dx = sin x + C
sec² x
∫sec² x dx = tan x + C
1/√(1−x²)
∫1/√(1−x²) dx = sin⁻¹x + C
1/(1+x²)
∫1/(1+x²) dx = tan⁻¹x + C

2. Techniques of Integration

Integration by Substitution
Let u = g(x) → du = g'(x)dx → rewrite ∫f(g(x))g'(x)dx as ∫f(u)du
Example: ∫2x(x²+1)⁵dx → u=x²+1, du=2x dx → ∫u⁵du = u⁶/6 + C = (x²+1)⁶/6 + C
Integration by Parts
∫u·dv = uv − ∫v·du
Choose u using LIATE: Logarithm, Inverse trig, Algebraic, Trigonometric, Exponential (u = first type found)

3. Definite Integrals & Properties

Fundamental Theorem
∫ₐᵇ f(x)dx = F(b) − F(a)
Reversal of Limits
∫ₐᵇ = −∫ᵦₐ
Additive Property
∫ₐᵇ = ∫ₐᶜ + ∫ᶜᵦ
Even Function (sym. interval)
∫₋ₐᵃ f(x)dx = 2∫₀ᵃ f(x)dx
Odd Function (sym. interval)
∫₋ₐᵃ f(x)dx = 0

4. Area Between Curves

Formula
Area = ∫ₐᵇ |f(x) − g(x)| dx
Where f(x) is the upper curve and g(x) is the lower curve between x=a and x=b. If curves cross, split the integral at intersection points.
💡 NET Focus
Identity proofs, double angle, and solving trig equations are most tested. Know the unit circle, special angle values, and compound angle formulas.

1. Special Angle Values

Angle30°45°60°90°
sin01/21/√2√3/21
cos1√3/21/√21/20
tan01/√31√3

2. Key Identities

Pythagorean
sin²θ + cos²θ = 1
1 + tan²θ = sec²θ
1 + cot²θ = cosec²θ
Compound Angle
sin(A±B) = sinA cosB ± cosA sinB
cos(A±B) = cosA cosB ∓ sinA sinB
Double Angle
sin 2A = 2 sinA cosA
cos 2A = cos²A−sin²A = 1−2sin²A
tan 2A = 2tanA/(1−tan²A)
Half Angle
sin²A = (1−cos2A)/2
cos²A = (1+cos2A)/2
Sum to Product
sinA+sinB = 2sin((A+B)/2)cos((A−B)/2)
tan(A±B)
tan(A±B) = (tanA±tanB)/(1∓tanA tanB)

3. General Solutions of Trig Equations

EquationGeneral Solution
sin θ = sin αθ = nπ + (−1)ⁿ α, n ∈ ℤ
cos θ = cos αθ = 2nπ ± α, n ∈ ℤ
tan θ = tan αθ = nπ + α, n ∈ ℤ

1. Straight Lines

Slope
m = (y₂−y₁)/(x₂−x₁) = −a/b (ax+by+c=0)
Distance
d = √[(x₂−x₁)²+(y₂−y₁)²]
Point to Line
d = |ax₁+by₁+c| / √(a²+b²)
Midpoint
((x₁+x₂)/2, (y₁+y₂)/2)
Parallel Lines
m₁ = m₂
Perpendicular Lines
m₁ × m₂ = −1

2. Circles

Standard Form
(x−h)²+(y−k)² = r²; center (h,k), radius r
General Form
x²+y²+2gx+2fy+c = 0
Center (−g,−f); r = √(g²+f²−c)
Tangent at Point
xx₁+yy₁+g(x+x₁)+f(y+y₁)+c = 0
Length of Tangent
√(x₁²+y₁²+2gx₁+2fy₁+c)

3. Conic Sections

ConicStandard EquationKey Features
Parabolay² = 4axFocus (a,0), Directrix x=−a, Axis: x-axis
Parabola (vertical)x² = 4ayFocus (0,a), Directrix y=−a
Ellipsex²/a² + y²/b² = 1 (a>b)Foci (±ae,0), e = c/a < 1
Hyperbolax²/a² − y²/b² = 1Foci (±ae,0), e > 1, asymptotes y=±(b/a)x

1. Matrices & Determinants

Determinant (2×2)
|A| = ad − bc for [[a,b],[c,d]]
Inverse (2×2)
A⁻¹ = (1/|A|) · [[d,−b],[−c,a]]
Cramer's Rule
x = Dₓ/D, y = D_y/D, z = D_z/D
Rank
Rank = number of non-zero rows in row-echelon form

2. Vectors

Magnitude
|v| = √(a²+b²+c²)
Dot Product
a·b = |a||b|cosθ = a₁b₁+a₂b₂+a₃b₃
Cross Product Magnitude
|a×b| = |a||b|sinθ
Unit Vector
â = a / |a|
Angle Between Vectors
cosθ = (a·b) / (|a||b|)
Perpendicularity
a·b = 0 ⟺ a ⊥ b

3. Probability

Classical Probability
P(A) = n(A) / n(S)
Addition Rule
P(A∪B) = P(A)+P(B)−P(A∩B)
Conditional Probability
P(A|B) = P(A∩B) / P(B)
Bayes' Theorem
P(A|B) = P(B|A)·P(A) / P(B)
Independent Events
P(A∩B) = P(A)·P(B)
Binomial Distribution
P(X=r) = ⁿCᵣ pʳ qⁿ⁻ʳ; mean=np; σ²=npq
💡 NET Focus
Mechanics is the largest Physics topic (~18–20 marks). Kinematics equations, Newton's laws, and energy conservation problems appear most frequently. Always draw free body diagrams.

1. Kinematics Equations (Constant Acceleration)

v = u + at
Final velocity = initial + (accel × time)
s = ut + ½at²
Displacement from initial position
v² = u² + 2as
Velocity-displacement relationship (no time)
s = (u+v)t/2
Displacement using average velocity
Projectile: Range
R = u²sin2θ / g
Projectile: Max Height
H = u²sin²θ / 2g

2. Newton's Laws & Applications

LawStatementFormula
1st (Inertia)Object stays at rest or constant velocity unless net force actsΣF = 0 → a = 0
2nd (Force)Net force equals mass times accelerationF = ma
3rd (Action-Reaction)Every action has equal and opposite reactionF₁₂ = −F₂₁
FrictionOpposing force at contact surfacef = μN (μ = coefficient)

3. Work, Energy & Power

Work
W = F·d·cosθ (J)
Kinetic Energy
KE = ½mv²
Potential Energy
PE = mgh
Work-Energy Theorem
W_net = ΔKE = KE_f − KE_i
Conservation of Energy
KE₁ + PE₁ = KE₂ + PE₂ (no friction)
Power
P = W/t = Fv (watts)

4. Momentum & Impulse

Momentum
p = mv (kg·m/s)
Impulse
J = FΔt = Δp
Conservation (Collision)
m₁u₁ + m₂u₂ = m₁v₁ + m₂v₂
Elastic Collision
KE conserved AND momentum conserved

5. Circular Motion & Gravitation

Centripetal Force
F_c = mv²/r = mω²r
Angular Velocity
ω = 2π/T = 2πf; v = ωr
Gravitational Force
F = Gm₁m₂/r² (G = 6.67×10⁻¹¹)
Orbital Velocity
v = √(GM/r); T² ∝ r³ (Kepler 3rd)

1. Simple Harmonic Motion (SHM)

Displacement
x = A sin(ωt + φ) or A cos(ωt + φ)
Velocity
v = ω√(A²−x²); max v = Aω at x=0
Acceleration
a = −ω²x (restoring; max at x=±A)
Period of Pendulum
T = 2π√(L/g)
Period of Spring-Mass
T = 2π√(m/k)

2. Wave Properties

Wave Speed
v = fλ
Wave Equation
y = A sin(2π/λ · x − 2πft)
Sound Speed (air, 0°C)
v = 331 m/s; increases 0.6 m/s per °C
Doppler Effect
f' = f·(v ± v_o)/(v ∓ v_s)
+ numerator: observer moves toward source; − denominator: source moves toward observer

3. Thermodynamics

1st Law of Thermodynamics
ΔU = Q − W (internal energy, heat, work)
Ideal Gas Law
PV = nRT (R = 8.314 J/mol·K)
Boyle's Law (const T)
P₁V₁ = P₂V₂
Charles's Law (const P)
V₁/T₁ = V₂/T₂
Gay-Lussac's Law (const V)
P₁/T₁ = P₂/T₂
Carnot Efficiency
η = 1 − T_cold/T_hot
💡 NET Focus
Ohm's law circuits, Kirchhoff's laws, capacitors, and magnetic force problems are very frequent. Know unit conversions: μF, mA, kΩ etc.

1. Electrostatics

Coulomb's Law
F = kq₁q₂/r² (k = 9×10⁹ N·m²/C²)
Electric Field
E = F/q = kq/r² (N/C or V/m)
Potential
V = kq/r (V); W = qV
Capacitance
C = Q/V = ε₀A/d (Farad, F)
Energy in Capacitor
U = ½CV² = Q²/2C
Capacitors in Parallel
C_total = C₁ + C₂ + ...
Capacitors in Series
1/C_total = 1/C₁ + 1/C₂ + ...

2. Current & Circuits

Ohm's Law
V = IR
Resistors in Series
R_total = R₁ + R₂ + ...
Resistors in Parallel
1/R_total = 1/R₁ + 1/R₂ + ...
Power
P = IV = I²R = V²/R (watts)
Kirchhoff's Current Law
ΣI_in = ΣI_out (at a node)
Kirchhoff's Voltage Law
ΣV = 0 around any closed loop

3. Magnetism & Electromagnetic Induction

Magnetic Force on Charge
F = qv × B = qvB sinθ
Force on Current
F = BIL sinθ
Faraday's Law
EMF = −dΦ/dt (Φ = BA cosθ)
Lenz's Law
Induced current opposes the change in flux

1. Optics

Snell's Law
n₁ sinθ₁ = n₂ sinθ₂
Refractive Index
n = c/v = sin i / sin r
Lens Formula
1/v − 1/u = 1/f
Magnification
m = v/u = h_i/h_o
Mirror Formula
1/v + 1/u = 1/f = 2/R
Young's Double Slit
fringe width β = λD/d

2. Modern Physics

Photoelectric Effect
E_photon = hf = hc/λ
KE_max = hf − φ
h = 6.626×10⁻³⁴ J·s; φ = work function
de Broglie Wavelength
λ = h/mv = h/p
Mass-Energy Equivalence
E = mc² (c = 3×10⁸ m/s)
Bohr's Model (H-atom)
E_n = −13.6/n² eV; r_n = 0.529n² Å
Radioactive Decay
N = N₀ e^(−λt); t_½ = 0.693/λ
💡 NET Focus
Physical chemistry (~50% of Chemistry marks) covers atomic structure, bonding, equilibrium, and electrochemistry. Know Kc/Kp expressions and how to apply Le Chatelier's principle.

1. Atomic Structure

Bohr's Radius
rₙ = 0.529 × n² / Z (Angstroms)
Energy Levels
Eₙ = −13.6 × Z² / n² (eV)
Quantum Numbers
n (shell), l (subshell), mₗ (orbital), mₛ (spin)
Max electrons in shell
2n² (n = 1,2,3…)

2. Chemical Bonding

Bond TypeBasisProperty
IonicElectron transfer between metals & nonmetalsHigh mp/bp, soluble in water, conducts when dissolved
CovalentShared electron pairs between nonmetalsLower mp/bp, poor conductor
MetallicSea of delocalized electronsMalleable, ductile, conducts electricity/heat
Hydrogen BondElectrostatic (N–H, O–H, F–H)Explains high bp of H₂O, NH₃, HF
Van der WaalsTemporary dipole–dipoleWeakest; increases with molecular mass

3. Chemical Equilibrium

Equilibrium Constant Kc
Kc = [products]^coeff / [reactants]^coeff
Kp from Kc
Kp = Kc(RT)^Δn (Δn = mol gas products − reactants)
Le Chatelier's Principle
System shifts to counter imposed change (pressure, temp, concentration)

4. Electrochemistry

Faraday's 1st Law
m = ZIt (Z = electrochemical equivalent)
Faraday's 2nd Law
m₁/m₂ = E₁/E₂ (E = equivalent weight)
Cell EMF
E°cell = E°cathode − E°anode
Nernst Equation
E = E° − (RT/nF) ln Q

5. Chemical Kinetics

Rate Law
Rate = k[A]^m[B]^n
Arrhenius Equation
k = Ae^(−Ea/RT)
Half Life (1st order)
t_½ = 0.693/k

1. Periodic Table Trends

PropertyAcross Period (→)Down Group (↓)
Atomic RadiusDecreasesIncreases
Ionization EnergyIncreasesDecreases
Electron AffinityIncreases (generally)Decreases (generally)
ElectronegativityIncreases (most electroneg: F)Decreases
Metallic CharacterDecreasesIncreases
Non-metallic CharacterIncreasesDecreases

2. s-Block & p-Block Elements

Group 1 — Alkali Metals
Very reactive, soft metals. React violently with water: 2Na + 2H₂O → 2NaOH + H₂. Reactivity increases down group. Stored in oil (Na, K).
Group 17 — Halogens
Strong oxidizing agents. Reactivity decreases: F > Cl > Br > I. Form HX acids with hydrogen. F₂ is the most electronegative element.
Group 2 — Alkaline Earth Metals
Less reactive than Group 1. BeO is amphoteric. Mg burns in CO₂. Ca reacts with water slowly. Ba is most reactive in group.
Group 18 — Noble Gases
Unreactive due to full valence shells. Used in lasers, lighting. Xe forms compounds (XeF₂, XeF₄) with highly electronegative elements.

3. Acids, Bases & Salts

pH Definition
pH = −log[H⁺]; pOH = −log[OH⁻]
pH + pOH at 25°C
pH + pOH = 14
Strong Acid (HCl, HNO₃)
Fully ionizes; [H⁺] = initial concentration
Buffer pH (Henderson)
pH = pKa + log([A⁻]/[HA])
💡 NET Focus
Reaction mechanisms, IUPAC naming, and isomerism are most tested in organic chemistry. Know the distinction between substitution, addition, and elimination reactions.

1. Hydrocarbons

ClassGeneral FormulaBondsKey Reaction
Alkanes (saturated)CₙH₂ₙ₊₂All single (C−C)Substitution (halogenation, light)
AlkenesCₙH₂ₙOne C=C double bondAddition (H₂, HX, X₂, H₂O)
AlkynesCₙH₂ₙ₋₂One C≡C triple bondAddition (2 steps possible)
Benzene/ArenesC₆H₆ + side chainsDelocalized π ringElectrophilic Aromatic Substitution

2. Functional Groups & Key Reactions

GroupFormulaClassKey Reaction
Hydroxyl−OHAlcoholOxidation → aldehyde/ketone; esterification with acids
Carbonyl (terminal)−CHOAldehydeOxidation → carboxylic acid; Tollens'/Fehling's test
Carbonyl (internal)C=OKetoneReduction → secondary alcohol; NOT oxidized by Tollens'
Carboxyl−COOHCarboxylic AcidEsterification; forms amides with amines
Amino−NH₂AmineBasicity; reacts with acids; forms amides
Halo−X (F,Cl,Br,I)Alkyl HalideNucleophilic substitution (SN1/SN2)

3. Isomerism

Structural Isomers
Same molecular formula, different structural connectivity. Types: chain, position, functional group isomerism. e.g. C₄H₁₀ → n-butane and isobutane.
Stereoisomers
Same connectivity, different spatial arrangement. Types: geometric (cis/trans) around C=C; optical isomers (enantiomers) around a chiral center (4 different groups).
💡 NET Focus
10 MCQs on English. Expect: sentence correction (grammar), synonym/antonym vocabulary, one-word substitution, and a short comprehension passage. Scoring all 10 is achievable with 3–4 days of prep.

1. Common Grammar Rules Tested

RuleWrongCorrect
Subject-Verb Agreement"The committee are meeting""The committee is meeting"
Pronoun Reference"Everyone must bring their book" (ambiguous)"Everyone must bring his/her book"
Parallel Structure"She likes running, to swim, and dance""She likes running, swimming, and dancing"
Modifier Placement"Running fast, the bus was missed""Running fast, she missed the bus"
Tense Consistency"He walked in and sits down""He walked in and sat down"

2. High-Frequency Vocabulary

Aberrant — deviating from normal Benign — gentle, harmless Cacophony — harsh noise Dearth — scarcity, shortage Ephemeral — short-lived Furtive — secretive, stealthy Gregarious — sociable Harbinger — forerunner, sign Impetuous — hasty, reckless Juxtapose — place side by side Laconic — brief, concise Melancholy — sadness Nefarious — wicked, criminal Obstinate — stubborn Pragmatic — practical Querulous — complaining Rancor — bitterness, resentment Sagacious — wise, shrewd Taciturn — silent, reserved Ubiquitous — present everywhere Venerate — to respect deeply Wane — to decrease, diminish

3. One-Word Substitutions

PhraseOne Word
One who can use both hands equally wellAmbidextrous
Fear of heightsAcrophobia
Study of animalsZoology
Words that sound the same but have different meaningsHomophones
Government by the peopleDemocracy
One who hates mankindMisanthrope
Medicine that counteracts poisonAntidote
Speech given at a funeralEulogy
💡 NET Focus
10 IQ/reasoning MCQs. Categories: number series, letter series, analogies, odd one out, coding-decoding, and logical deduction. These are fully solvable with pattern recognition — no subject knowledge needed.

1. Number Series — Pattern Types

Pattern TypeExample SeriesRule
Arithmetic (add/sub)3, 7, 11, 15, ?+4 each time → 19
Geometric (multiply)2, 6, 18, 54, ?×3 each time → 162
Square pattern1, 4, 9, 16, ?n² → 25
Cube pattern1, 8, 27, 64, ?n³ → 125
Difference of differences1, 2, 4, 7, 11, ?Differences: 1,2,3,4,5 → 16
Alternating series2, 5, 3, 6, 4, 7, ?Two interleaved APs → 5

2. Analogies — How to Solve

1
Identify the Relationship
Part-whole? Cause-effect? Function? Category? Synonyms? Worker-tool? Action-result?
2
Form a Precise Sentence
e.g., "A pen is a tool used by a writer." Then apply: "A ___ is a tool used by a surgeon." → Scalpel.
3
Test All Options
Don't stop at first plausible answer. The best answer fits the relationship most precisely.

3. Coding-Decoding Tips

Letter Shift
If A=1, B=2 … Z=26, then reverse coding is Z=1, Y=2 etc. Count forward or backward in the alphabet. Always check if the shift is consistent.
Positional Coding
If MANGO = 13,1,14,7,15 (position in alphabet), then same logic applies. Reverse positions: A=26, B=25. Check both forward and reverse mappings.

4. Logical Deduction

Syllogism Method

Step 1: Convert both premises to standard form (All/Some/No A are B).

Step 2: Draw a Venn diagram quickly.

Step 3: Only accept a conclusion that is definitely true in all possible Venn diagrams — if it's only possibly true, it doesn't follow.

Key rule: "Some A are B" does NOT mean "Some B are A" is false — it may be true. But "All A are B" does imply "Some A are B".

Worked Example — Syllogism
All engineers are graduates. Some graduates are doctors. Conclusion: Some engineers are doctors?
Draw: Engineers ⊂ Graduates; Doctors ∩ Graduates ≠ ∅ (partial overlap)
The overlap of Graduates & Doctors may or may not include Engineers — not guaranteed
Conclusion does NOT follow — it is possible but not certain.