CHEMISTRY LECTURE

JAMB CHEMISTRY LECTURE

1. Separation of Mixtures and Purification

(a) Pure and Impure Substances

A pure substance contains only one type of particle (element or compound), while an impure substance (mixture) contains two or more substances physically combined.

• Pure substances have fixed melting and boiling points.
• Impure substances melt over a range.

(b) Boiling and Melting Points

Pure substances have sharp melting points. Impurities lower melting point and increase boiling range.

(c) Elements, Compounds, Mixtures

• Element: Cannot be broken chemically (e.g., O₂)
• Compound: Chemically combined (e.g., H₂O)
• Mixture: Physically combined (e.g., sand + salt)

(d) Physical vs Chemical Changes

• Physical: No new substance (melting ice)
• Chemical: New substance formed (burning)

(e) Separation Techniques

• Evaporation – recovering solute
• Distillation – separating liquids
• Fractional Distillation – different boiling points
• Filtration – solid from liquid
• Chromatography – separates based on movement
• Sublimation – solid → gas (e.g., iodine)
• Decantation – pouring off liquid

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2. Chemical Combination (Stoichiometry)

Laws

• Law of Conservation: Mass is neither created nor destroyed
• Definite Proportion: Same ratio always
• Multiple Proportion: Simple ratios
• Gay Lussac: Volumes combine in ratios
• Avogadro: Equal volumes → equal molecules

Mole Concept

1 mole = 6.02 × 10²³ particles

Example 1

Calculate moles in 44g of CO₂

Molar mass CO₂ = 44 Moles = 44 / 44 = 1 mole

Example 2

Calculate number of molecules in 2 moles of O₂

= 2 × 6.02 × 10²³ = 1.204 × 10²⁴ molecules

Stoichiometric Calculation

2H₂ + O₂ → 2H₂O

If 4 moles of H₂ react: Ratio H₂:H₂O = 2:2 → 4 moles produce 4 moles H₂O

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3. Concentration Calculations

g/dm³

Mass concentration = mass / volume

Example: 10g in 2dm³ = 10 / 2 = 5 g/dm³

mol/dm³

Molar concentration = moles / volume

Example: 0.5 moles in 0.25dm³ = 0.5 / 0.25 = 2 mol/dm³

Conversion (25cm³ → 1000cm³)

Factor = 1000 / 25 = 40 Multiply concentration by 40

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4. Kinetic Theory of Matter

• Particles are always moving
• Higher temperature → faster motion

States Explained

• Melting: solid → liquid
• Boiling: liquid → gas
• Freezing: liquid → solid
• Condensation: gas → liquid

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5. Gas Laws

Boyle's Law

P₁V₁ = P₂V₂

Example: P₁ = 2 atm, V₁ = 4 dm³ P₂ = ?, V₂ = 2 dm³

2 × 4 = P₂ × 2 P₂ = 4 atm

Charles Law

V₁/T₁ = V₂/T₂

Ideal Gas Equation

PV = nRT

Example: P = 1 atm, V = 22.4 dm³, R = 0.0821, T = 273K

n = PV / RT = (1 × 22.4) / (0.0821 × 273) = 1 mole

Vapour Density

VD = Molar Mass / 2

Example: VD = 14 Molar mass = 2 × 14 = 28

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EXAM SUMMARY

• Use mole = mass / molar mass
• Use PV = nRT for gases
• Always balance equations
• Convert cm³ to dm³ (÷1000)
• Use correct separation method

CHEMISTRY CBT

JAMB Chemistry CBT Practice – 40 Questions

Time Left: 900 sec

USE OF ENGLISH CBT

Time: 0 seconds

CRS JAMB LECTURE

JAMB CRS LECTURE: MORAL ISSUES & CHRISTIAN LIVING

1. Sexual Immorality

(a) Prostitution

1 Corinthians 6:16-20: Believers’ bodies are temples of the Holy Spirit; joining with a prostitute defiles the body.

Proverbs 7:10-27: Describes the seductive nature and destructive end of prostitution.

Proverbs 23:27-28: A prostitute is a deep pit leading to destruction.

Lessons:

• Christians must avoid sexual immorality.
• The body belongs to God.
• Immorality leads to spiritual and physical destruction.

(b) Adultery and Fornication

Hebrews 13:4: Marriage should be honored; adulterers will be judged.

Ephesians 5:3-10: No sexual immorality should be found among believers.

Matthew 5:28-32: Lust is equivalent to adultery in the heart.

Deuteronomy 22:22: Adultery was punishable by death under the law.

Leviticus 20:10: Both parties in adultery face judgment.

Lessons:

• Sex is sacred within marriage.
• Even immoral thoughts are sinful.
• God judges sexual sins.

(c) Homosexuality

Romans 1:24-32: Describes moral decline and unnatural relations.

Leviticus 18:21-30: Prohibits sexual practices considered abominable.

Leviticus 20:13: States consequences under the law.

Lessons:

• Christians are called to moral purity.
• Sin separates man from God.
• Repentance restores relationship with God.

2. Corruption

1 Timothy 6:6-11: Love of money is the root of evil.

2 Timothy 3:1-8: Describes corrupt people in the last days.

2 Timothy 3:8: Corrupt minds oppose the truth.

Lessons:

• Contentment is key to godliness.
• Greed leads to destruction.
• Christians must uphold integrity.

3. Christian Living in the Community

(a) Interpersonal Relationships Among Christians

1 Peter 5:1-4: Leaders should serve willingly.

Romans 12:3-21: Love sincerely, live in peace.

Hebrews 13:1-21: Show love, hospitality, and obedience.

• Love one another genuinely
• Be humble and peaceful
• Help those in need

(b) Christians Living Among Non-Christians

1 Peter 2:11-25: Live good lives among unbelievers.

Romans 15:1-2: Bear with the weak and build others up.

• Be good examples
• Avoid retaliation
• Promote peace

(c) Christian Attitude to Persecution

1 Peter 1:5-9: Trials strengthen faith.

1 Peter 4:1-19: Rejoice in suffering for Christ.

1 Peter 3:13-22: Suffer for doing good.

• Remain steadfast in faith
• Rejoice in persecution
• Trust God always

(d) Relationship in the Christian Family

Ephesians 6:1-9: Children obey parents; parents guide in love.

Colossians 3:18-21: Mutual respect in the family.

1 Peter 3:1-7: Harmony between husband and wife.

• Love and respect in family
• Obedience and discipline
• Peaceful coexistence

4. Effective Prayer

James 1:2-8: Pray with faith, not doubting.

James 4:1-3: Wrong motives hinder prayer.

James 5:13-18: Prayer of a righteous man is powerful.

Matthew 6:5-13: Jesus teaches the Lord’s Prayer.

Key Points on Prayer:

• Pray with sincerity and faith
• Avoid hypocrisy
• Pray according to God’s will
• Righteous living enhances prayer

The Lord’s Prayer (Summary)

• Worship God
• Seek His kingdom
• Ask for daily needs
• Seek forgiveness
• Ask for protection

EXAM FOCUS (JAMB)

• Know key scriptures and their teachings
• Understand moral lessons from each passage
• Apply teachings to modern society
• Differentiate between similar concepts (e.g., adultery vs fornication)

PHYSICS CBT

Physics CBT (40 Questions)

Time: 0s

PHYSICS LECTURE

PHYSICS LECTURE: MEASUREMENT & MOTION

1. Length, Area and Volume

SI unit of length = metre (m)

Vernier Calipers Example

Main scale reading = 2.3 cm
Vernier reading = 0.07 cm
Total length = 2.3 + 0.07 = 2.37 cm

Micrometer Screw Gauge Example

Pitch = 0.5 mm, Head scale = 25 divisions
Reading = 2.5 mm + (25 × 0.01) = 2.5 + 0.25 = 2.75 mm

Volume Calculation

Cube of side 4 cm
Volume = 4 × 4 × 4 = 64 cm³

2. Mass

SI unit = kilogram (kg)

If object balances with 200g + 50g weights,
Mass = 250 g

3. Time

SI unit = second (s)

Time taken for 20 oscillations = 40 s
Period = 40/20 = 2 s

4. Fundamental & Derived Quantities

Fundamental: Length, Mass, Time

Derived: Velocity, Density

Density = Mass/Volume
= 2kg / 0.5m³ = 4 kg/m³

5. Dimensions

Velocity = m/s = LT⁻¹

6. Errors & Significant Figures

Measured length = 5.2 cm ± 0.1 cm

7. Scalars and Vectors

Scalar: speed, mass

Vector: velocity, force

Resolve 10N at 30°:
Horizontal = 10cos30 = 8.66N
Vertical = 10sin30 = 5N

8. Motion

Types: translational, rotational, oscillatory

9. Linear Motion

Use equation v = u + at
u = 0, a = 2m/s², t = 5s
v = 0 + (2×5) = 10 m/s

s = ut + 1/2 at²
s = 0 + 1/2 × 2 × 25 = 25 m

10. Projectile Motion

Velocity = 20m/s at 30°
Time of flight = (2u sinθ)/g = (2×20×0.5)/10 = 2 s

Range = (u² sin2θ)/g = (400 × sin60)/10 = 34.6 m

11. Newton's Laws

F = ma
F = 5kg × 2m/s² = 10 N

Momentum = mv = 2kg × 3m/s = 6 kgm/s

12. Circular Motion

Centripetal force = mv²/r
= 2×(4²)/2 = 16 N

13. Simple Harmonic Motion

T = 2π√(l/g)
l = 1m
T = 2×3.14×√(1/10) = 2 s approx

Government 4 CBT

JAMB Government CBT Quiz - 40 Questions

Time: 05:00

Government 4 lecture

JAMB Government Fully Detailed Lecture

1. Systems of Government

a. Presidential System

• Features: Head of State = Head of Government; fixed term; separation of powers; direct election of president.
• Reasons for adoption: Prevent abuse of power, ensure accountability, provide stable leadership.
• Merits: Clear separation of powers, stable executive, direct accountability to citizens.
• Demerits: Risk of executive-legislative deadlock, rigidity in removing president, expensive elections.

b. Parliamentary System

• Features: Prime Minister = Head of Government; Head of State separate; government depends on parliamentary confidence; collective responsibility.
• Reasons for adoption: Promote government efficiency, flexibility, responsiveness to legislature.
• Merits: Quick decision-making, easier to remove ineffective government, closer link with legislature.
• Demerits: Prime Minister may be too powerful, unstable if parliament fragmented, executive dependent on majority support.

c. Monarchical System

• Features: Head of State is hereditary; can be absolute or constitutional; may coexist with parliamentary system.
• Reasons for adoption: Tradition, continuity, national unity, symbolic leadership.
• Merits: Stability, continuity of leadership, symbol of national identity.
• Demerits: May be undemocratic, succession problems, potential abuse of power in absolute monarchies.

d. Unitary System

• Features: Centralized power; local units dependent on central government.
• Reasons for adoption: National unity, quick decision-making, uniform laws.
• Merits: Efficient policy implementation, uniform governance, strong central control.
• Demerits: Local needs ignored, risk of central authority abuse, less local participation.

e. Federal System

• Features: Power shared between central and regional governments; constitution defines powers; dual citizenship in some cases.
• Reasons for adoption: Manage diversity, balance power, allow regional autonomy.
• Merits: Protects minority interests, encourages local participation, prevents central domination.
• Demerits: Conflicts over powers, duplication of government structures, expensive governance.

f. Confederal System

• Features: Member states retain sovereignty; central authority weak; loose cooperation.
• Reasons for adoption: Desire for independence, preserve state autonomy.
• Merits: States retain freedom, flexible cooperation, easy to dissolve alliance if needed.
• Demerits: Weak central government, coordination problems, vulnerability to external threats.

2. Political and Economic Ideologies

• Communalism: Collective ownership of property; emphasizes community welfare.
  Merits: Promotes equality, social cohesion, shared responsibility.
  Demerits: Low individual incentive, possible inefficiency.
• Feudalism: Hierarchical land-based system; lords and vassals.
  Merits: Orderly social hierarchy, loyalty bonds.
  Demerits: Exploitation of peasants, rigid social structure.
• Capitalism: Private ownership, profit-driven, market economy.
  Merits: Innovation, individual freedom, wealth creation.
  Demerits: Inequality, exploitation, market failures.
• Socialism: State involvement, redistribution, welfare.
  Merits: Reduces inequality, social welfare, public ownership.
  Demerits: Bureaucracy, risk of inefficiency, limits individual initiative.
• Communism: Classless society, collective ownership.
  Merits: Equality, elimination of exploitation.
  Demerits: Suppression of private enterprise, possible authoritarianism.
• Totalitarianism: Absolute state control, suppression of opposition.
  Merits: Quick decisions, unity of purpose.
  Demerits: Human rights violations, lack of freedoms.
• Fascism: Extreme nationalism, authoritarian control.
  Merits: Strong state, national unity.
  Demerits: Oppression, militarism, suppression of dissent.
• Nazism: Fascism with racial ideology.
  Merits: None socially ethical.
  Demerits: Racism, genocide, authoritarian rule.

3. Constitution and Law

• Meaning: Supreme law of a nation.
• Sources: Legislation, custom, judicial decisions.
• Functions: Limits government power, protects rights, defines structure.
• Types: Written vs Unwritten; Rigid (hard to amend) vs Flexible (easy to amend).
• Merits of Written Constitution: Clarity, legal certainty, stable.
• Demerits: Rigidity, hard to change.
• Merits of Unwritten Constitution: Flexible, adaptable.
  Demerits: Uncertainty, may be misinterpreted.
• Ethics & Accountability: Ensures public office holders act responsibly.
• Separation of Powers & Checks and Balances: Prevents abuse of power.
  Merits: Limits authoritarianism, promotes democracy.
  Demerits: Possible gridlock, delays decision-making.
• Individual & Collective Responsibility: Everyone accountable.
• Constitutionalism & Rule of Law: Government operates within law.
• Legislative Enactments: Acts, edicts, bye-laws, delegated legislation, decrees.
  Merits: Law-making clarity; Demerits: Misuse by legislature possible.

4. Citizenship

• Meaning: Legal membership of a state.
• Types: By birth, naturalization, registration.
• Rights: Civil, political, social, economic.
• Dual Citizenship: Holding citizenship of two countries; may require renunciation.
  Merits: International mobility; Demerits: Conflicts of loyalty.
• Duties & Obligations of Citizens: Obey laws, pay taxes, participate in governance.
  Merits: Promotes national development; Demerits: Citizens may neglect duties.
• Duties & Obligations of State: Protect citizens, provide security, welfare.
  Merits: Stability, trust in government; Demerits: Poor implementation may cause unrest.

5. Electoral System

• Suffrage: Right to vote. Evolution: Limited → Universal. Types: Direct, Indirect.
• Election: Selection of representatives. Types: General, By-election. Ingredients of free & fair elections: Transparency, impartiality, accountability.
• Electoral Systems:
  • First-Past-The-Post: Simple, clear results.
    Merits: Easy, quick; Demerits: May not reflect majority choice.
  • Proportional Representation: Seats based on votes.
    Merits: Fairer representation; Demerits: Complex, coalition governments.
  • Mixed Systems: Combines both.
    Merits: Balanced; Demerits: Complexity, disputes.
• Electoral Commission: Supervises elections.
  Merits: Ensures free & fair process; Demerits: Corruption, political interference.

Summary

This lecture covers all aspects of government for JAMB with definitions, features, reasons, merits and demerits, functions, and examples. Key topics include:

• Systems of government (Presidential, Parliamentary, Monarchical, Unitary, Federal, Confederal)
• Political and economic ideologies (Communalism, Feudalism, Capitalism, Socialism, Communism, Totalitarianism, Fascism, Nazism)
• Constitution and law (types, functions, ethics, accountability)
• Citizenship (rights, duties, dual citizenship)
• Electoral systems (suffrage, election, electoral commission)

This is now fully detailed for **exam-ready JAMB revision**.

LITERATURE TEXT CBT

JAMB CBT - Antony and Cleopatra

Time: 20:00

LITERATURE TEXT LECTURE

JAMB LITERATURE (DETAILED LECTURE)

ANTONY AND CLEOPATRA

Author: William Shakespeare
Genre: Tragedy
Setting: Rome and Egypt

1. DETAILED PLOT BREAKDOWN

Beginning (Exposition):
Mark Antony, a Roman leader, abandons his political duties and lives in Egypt with Cleopatra. He indulges in pleasure and luxury, ignoring responsibilities.

Conflict Begins:
News reaches Antony that his wife is dead and Pompey is preparing war. This awakens his sense of duty and he returns to Rome.

Political Tension:
In Rome, Antony clashes with Octavius Caesar. To maintain peace, he marries Octavia, Caesar’s sister. However, this marriage is political, not emotional.

Turning Point:
Antony returns to Cleopatra, abandoning Octavia. This decision marks the beginning of his downfall.

Rising Conflict:
War breaks out between Antony and Octavius. Antony ignores wise advice and chooses to fight at sea.

Climax:
During battle, Cleopatra’s fleet withdraws. Antony follows her, causing a major defeat. This shows his emotional weakness.

Falling Action:
Antony loses respect, his soldiers desert him, and Enobarbus betrays him. Antony becomes unstable.

Tragic Ending (Resolution):
Antony believes Cleopatra betrayed him and attempts suicide. He dies in her arms. Cleopatra later commits suicide to avoid humiliation. Octavius becomes the sole ruler.

2. SETTING (DETAILED)

Rome:

• Represents discipline, order, duty, and power
• Associated with logic and military strength
• Octavius symbolizes Rome

Egypt (Alexandria):

• Represents pleasure, luxury, emotions, and love
• Associated with beauty and enjoyment
• Cleopatra symbolizes Egypt

Significance:
The contrast between Rome and Egypt reflects Antony’s internal conflict between duty and desire.

3. THEMES (FULL EXPLANATION)

Love vs Duty:
Antony abandons his responsibilities for Cleopatra. His inability to balance both leads to his downfall.

Power and Ambition:
Octavius seeks total control of Rome. His ambition leads him to eliminate rivals.

Betrayal and Loyalty:
Enobarbus betrays Antony, and Antony suspects Cleopatra. Loyalty is constantly tested.

Tragedy and Fate:
The characters cannot escape their destiny. Their flaws lead them to destruction.

Pride:
Cleopatra chooses death rather than humiliation. Antony refuses to accept defeat.

4. CHARACTER ANALYSIS (DETAILED)

Mark Antony:

• Brave and respected soldier
• Weak due to excessive love
• Makes poor decisions
• Tragic hero with a fatal flaw (love)

Cleopatra:

• Beautiful, intelligent, and manipulative
• Emotionally expressive
• Values pride and dignity
• Chooses death over disgrace

Octavius Caesar:

• Calm, strategic, and disciplined
• Represents political control
• Emotionally reserved

Enobarbus:

• Loyal but realistic
• Leaves Antony due to poor leadership
• Dies from guilt

Octavia:

• Peaceful and loyal
• Used as a political tool

5. STYLE & LANGUAGE

• Use of poetic language and imagery
• Contrast between Roman seriousness and Egyptian passion
• Dramatic irony (audience knows more than characters)
• Symbolism (Rome vs Egypt)

6. TONE AND MOOD

• Tone: Serious, tragic, emotional
• Mood: Romantic, tense, sorrowful

7. DRAMATIC STRUCTURE

• Exposition – Antony in Egypt
• Rising Action – Conflict begins
• Climax – Naval defeat
• Falling Action – Betrayal and despair
• Resolution – Death of lovers

8. MORAL LESSONS (EXPLAINED)

• Excessive pleasure leads to destruction
• Leaders must control emotions
• Pride can cause downfall
• Bad decisions destroy great people

9. QUICK REVISION

Antony chooses Cleopatra over duty, loses power, and dies. Cleopatra kills herself to avoid humiliation. Octavius becomes ruler.

Practical chemistry CBT

Chemistry Lecture Quiz

Theory Questions (15)

1. Define concentration and explain its units.

Concentration measures the amount of solute per unit volume of solution, commonly expressed in mol/L (Molarity) or g/L.

2. What is the difference between strong and weak acids?

Strong acids ionize completely in solution; weak acids ionize partially.

3. Explain the role of indicators in titrations.

Indicators show the end point of a titration by changing color when the reaction is complete.

4. When would you use methyl orange instead of phenolphthalein?

Use methyl orange for strong acid-strong base titrations or strong acid-weak base, because it changes color in acidic pH.

5. What are the color changes of methyl orange in acid and base?

Acid: Red, Base: Yellow.

6. What are the color changes of phenolphthalein in acid and base?

Acid: Colorless, Base: Pink.

7. What is the purpose of a rough titration?

A rough titration determines approximately the volume of titrant needed before performing accurate titrations.

8. Explain how to calculate the average titre.

Average titre = sum of accepted titres ÷ number of accepted titres, only using titres within ±0.2 cm³ difference.

9. Why should the difference between two accepted titres be within ±0.2?

To ensure accuracy and precision; larger differences indicate experimental error.

10. Explain the difference between primary and secondary standard solutions.

Primary standards are pure and stable; secondary standards are standardized against primary standards.

11. How does temperature affect titration reactions?

Temperature can change reaction rate and solubility, affecting the endpoint accuracy.

12. Define molarity and normality.

Molarity (M) = moles of solute per liter; Normality (N) = equivalents of solute per liter.

13. What is the significance of the end point in titration?

The end point indicates the reaction is complete and allows calculation of concentrations.

14. Describe the procedure for preparing a standard solution.

Weigh pure solute accurately, dissolve in solvent, and dilute to a known volume in a volumetric flask.

15. Why is it important to rinse the burette before titration?

To remove impurities and ensure the titrant does not get diluted or contaminated.

Calculation Questions (10)

1. Calculate the molarity of a solution when 25cm³ of 0.1M NaOH neutralizes 50cm³ of HCl.

Molarity of HCl = (0.1 × 25)/50 = 0.05 M

2. Determine the concentration of H2SO4 if 30cm³ reacts with 20cm³ of 0.2M NaOH.

H2SO4 + 2NaOH → Na2SO4 + 2H2O. M1V1 = 2M2V2 → M1 = (0.2 × 20 × 2)/30 = 0.267 M

3. Calculate the number of moles in 0.5L of 2M HCl.

Moles = M × V = 2 × 0.5 = 1 mole

4. Find the mass of NaOH required to prepare 250cm³ of 0.1M solution.

Moles = 0.1 × 0.25 = 0.025 moles. Mass = 0.025 × 40 = 1 g

5. Determine the volume of 0.2M HCl needed to react with 0.1g of Na2CO3.

Moles Na2CO3 = 0.1/106 ≈ 0.000943. HCl + Na2CO3 → 2HCl per 1 Na2CO3 → V = (0.000943×2)/0.2 ≈ 0.00943 L = 9.43 mL

6. Calculate molarity from given titration data: 25cm³ acid, 0.1M base, titre = 23.5cm³.

M1V1 = M2V2 → M1 = (0.1×23.5)/25 ≈ 0.094 M

7. Find the concentration of acetic acid if 50cm³ reacts with 25cm³ of 0.1M NaOH.

M1V1 = M2V2 → M1 = (0.1×25)/50 = 0.05 M

8. Determine moles of HCl in 100cm³ of 0.5M solution.

Moles = 0.5 × 0.1 = 0.05 moles

9. Calculate the titre average if three accepted values are 24.1, 24.3, and 24.2cm³.

Average = (24.1 + 24.3 + 24.2)/3 = 24.2 cm³

10. Find the normality of H2SO4 if 25cm³ reacts with 20cm³ of 0.1N NaOH.

H2SO4 + 2NaOH → N1V1 = 2N2V2 → N1 = (2×0.1×20)/25 = 0.16 N

Titration Tables (5)

Practical chemistry lecture

WAEC 2026 CHEMISTRY PRACTICAL – VOLUMETRIC ANALYSIS

1. Concentration Concepts (mol/dm³ and g/dm³)

Definitions:

• Mol/dm³: Number of moles of solute per 1 dm³ solution.
• g/dm³: Mass of solute per 1 dm³ solution.

Formulas:

Molarity (M) = moles / volume(dm³)
Moles = mass / molar mass
g/dm³ = M × molar mass

Example 1: Concentration in 25 cm³

5g NaOH dissolved in 25 cm³ solution. Find molarity in mol/dm³.

Volume = 25 ÷ 1000 = 0.025 dm³

Moles = 5 ÷ 40 = 0.125 mol

Molarity = 0.125 ÷ 0.025 = 5.0 mol/dm³

Example 2: Convert concentration to 1000 cm³

Concentration in 25 cm³ = 0.5 mol/dm³. Concentration in 1000 cm³ = 0.5 × 1000 ÷ 25 = 20 mol

Example 3: Pure vs Impure substance

Substance weighed = 5g, purity = 80%

Actual pure mass = 5 × 0.80 = 4g

Moles = 4 ÷ 40 = 0.1 mol

Molarity in 100 cm³ (0.1 dm³) solution = 0.1 ÷ 0.1 = 1 mol/dm³

2. Acid-Base Titration – Stepwise Workflow

Only titres differing by ±0.20 cm³ are accepted to calculate the average. Outliers are discarded.

Example: Strong Acid (HCl) vs Strong Base (NaOH)

Titre Type	Volume Acid (cm³)	Volume Base (cm³)	Notes
Rough Titre	19.5	24.0	Estimate endpoint; not used in average
1st Accurate	20.0	25.0	Accepted if difference with 2nd titre ≤ ±0.20
2nd Accurate	19.8	25.0	Accepted if difference with 1st ≤ ±0.20
3rd Accurate	20.3	25.0	Rejected: difference with 2nd = 0.5 > 0.2

Accepted titres: 1st and 2nd (20.0 & 19.8)
Average = (20.0 + 19.8) / 2 = 19.9 cm³

Molarity Calculation: M₁V₁ = M₂V₂ → 0.10 × 25/1000 = M × 19.9/1000 → M ≈ 0.1256 mol/dm³

Weak Acid (CH₃COOH) vs Strong Base (NaOH)

Titre Type	Volume Acid (cm³)	Volume Base (cm³)	Notes
Rough Titre	24.5	29.5	Estimate endpoint
1st Accurate	25.0	30.0	Accepted if difference ≤ ±0.20 cm³
2nd Accurate	24.8	30.0	Accepted (diff = 0.2 cm³)
3rd Accurate	25.3	30.0	Rejected (diff with 2nd = 0.5 cm³ > 0.2)

Average accepted titre: (25.0 + 24.8)/2 = 24.9 cm³

Molarity: M × 24.9/1000 = 0.10 × 30/1000 → M ≈ 0.1205 mol/dm³

3. Indicators in Acid-Base Titration

• Methyl Orange: Acid → Red, Base → Yellow, Neutral → Orange
• Phenolphthalein: Acid → Colorless, Base → Pink, Neutral → Slight Pink
• Methyl Red: Acid → Red, Base → Yellow, Neutral → Orange

Choose indicator according to acid/base type to detect correct endpoint.

4. Percentage Purity & Yield

% purity = (actual / expected) × 100

Example: Expected = 5g, Actual = 4g → % purity = 80%

% yield = (actual / theoretical) ×100

Example: Theoretical yield = 6g, Actual = 4.8g → % yield = 80%

5. Practical Tips

• Always perform a rough titre first.
• Take at least 2–3 accurate titres.
• Only use titres with difference ≤ ±0.20 cm³ for average.
• Read burette at eye level; record to 0.01 cm³.
• Rinse apparatus with solution before titration.
• Choose indicator based on acid/base strength.
• Convert all cm³ volumes to dm³ before calculations.

USE OF ENGLISH CBT

JAMB Use of English CBT (40 Questions)

Time: 0s

USE OF ENGLISH LECTURE

JAMB USE OF ENGLISH – ADVANCED MASTERCLASS

1. SYNONYMS

Definition: Lexical items exhibiting semantic proximity, though nuanced by contextual constraints.

Examples:
1. Abundant – Plentiful
2. Candid – Frank
3. Diligent – Industrious
4. Eloquent – Articulate
5. Frugal – Economical
6. Gregarious – Sociable
7. Hostile – Antagonistic
8. Imminent – Impending

JAMB Insight: Synonymy is rarely absolute; contextual compatibility determines correctness.

2. ANTONYMS

Definition: Lexical oppositions reflecting semantic contrast.

Examples:
1. Benevolent – Malevolent
2. Cursory – Thorough
3. Dormant – Active
4. Euphoria – Misery
5. Fragile – Robust
6. Lucid – Obscure
7. Optimistic – Pessimistic
8. Transient – Permanent

3. HOMONYMS

Definition: Phonologically identical or similar words with divergent meanings.

Examples:
1. Bare / Bear
2. Break / Brake
3. Complement / Compliment
4. Desert / Dessert
5. Principal / Principle
6. Stationary / Stationery
7. Sight / Site / Cite
8. Weather / Whether

4. CLAUSE & SENTENCE PATTERNS

Clause: A syntactic unit containing a subject and predicate.

Types:
- Independent Clause
- Dependent Clause

Sentence Patterns:
1. S + V → The child laughed.
2. S + V + O → She wrote a letter.
3. S + V + C → He became a doctor.
4. S + V + IO + DO → She gave him money.
5. S + V + O + C → They elected him president.
6. Complex sentence structures
7. Compound sentence coordination
8. Compound-complex constructions

5. WORD CLASSES & FUNCTIONS

Lexical Categories:

1. Noun – entity (teacher)
2. Verb – action/state (run, be)
3. Adjective – qualifier (beautiful)
4. Adverb – modifier (quickly)
5. Pronoun – substitution (they)
6. Preposition – relation (under)
7. Conjunction – linkage (however)
8. Interjection – exclamation (alas!)

Each performs syntactic and semantic functions within discourse.

6. GRAMMATICAL SYSTEMS

Tense:
1. Present – writes
2. Past – wrote
3. Future – will write

Aspect:
- Progressive – is writing
- Perfect – has written

Agreement:
1. He runs ✔
2. They run ✔

Degree:
1. Positive – tall
2. Comparative – taller
3. Superlative – tallest

Question Tags:
1. She sings, doesn’t she?
2. They left, didn’t they?

7. PUNCTUATION & SPELLING

Core Marks:
1. Comma (,)
2. Full stop (.)
3. Colon (:)
4. Semicolon (;)
5. Apostrophe (’)
6. Quotation marks (“ ”)
7. Question mark (?)
8. Exclamation mark (!)

Spelling Distinctions:
1. Affect / Effect
2. Accept / Except
3. Advice / Advise
4. Practice / Practise
5. Licence / License
6. Loose / Lose
7. Principal / Principle
8. Their / There / They’re

8. USAGE TYPES

Ordinary Usage: literal expression
Figurative Usage: metaphorical extension
Idiomatic Usage: culturally fixed meaning

Examples:
1. Break the ice
2. Spill the beans
3. Hit the nail on the head
4. Under the weather
5. Once in a blue moon
6. A blessing in disguise
7. Burn the midnight oil
8. Bite the bullet

9. PHONETICS

Vowels:
Monophthongs – /i:/, /e/, /æ/
Diphthongs – /ai/, /ei/, /ɔi/

Consonants:
Clusters – /str/, /bl/, /tr/

Rhymes:
1. Light / Sight
2. Man / Can
3. Day / Say
4. Book / Cook
5. Time / Rhyme
6. Pen / Hen
7. Ball / Call
8. Tree / Free

Word Stress:
REcord (noun)
reCORD (verb)

Intonation:
Rising tone – question
Falling tone – statement

GOVT3CBT

JAMB Government CBT (40 Questions)

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