ORGANIC CHEMISTRYCBT

Organic Chemistry CBT (40 Questions)

ORGANIC CHEMISTRY4

Organic Chemistry Interactive Lab

Simple Molecular Visualizer (Methane)

IUPAC Name Generator

Number of Carbon Atoms (1–10)

Functional Group Detector

Enter Chemical Formula

Reaction Predictor

Combustion Hydrogenation Esterification

Organic Chemistry Mini Quiz

Score: 0

1. Functional group of alcohol?

-OH -COOH -CHO

2. Formula of alkanes?

CnH₂n+2 CnH₂n CnH₂n−2

IRGANIC CHEMISTRY3

Functional Group Identification Tool

Select Functional Group Alkane Alkanol (Alcohol) Alkanal (Aldehyde) Alkanone (Ketone) Alkanoic Acid Ester

ORGANIC CHEMISTRY2

Organic Chemistry Reaction Mechanisms

1. Nucleophilic Substitution (SN1)

Halogenoalkane reacts with hydroxide ion to form alcohol.

2. Electrophilic Addition

Ethene reacts with hydrogen bromide.

3. Esterification

Ethanoic acid reacts with ethanol.

ORGANIC CHEMISTRY1

ORGANIC CHEMISTRY

1. Tetravalency of Carbon

Carbon is a unique element capable of forming four covalent bonds with other atoms. This property is known as tetravalency. Carbon has an atomic number of 6 with electronic configuration 2,4, meaning it has four electrons in its outer shell.

Because carbon requires four more electrons to achieve stability, it forms four covalent bonds with other atoms such as hydrogen, oxygen, nitrogen or other carbon atoms.

Methane Structure (CH₄)

2. Homologous Series

A homologous series is a group of organic compounds with similar chemical properties, the same functional group, and successive members differing by CH₂.

Series	General Formula	Functional Group	Example
Alkanes	CnH₂n+2	Single bond	Methane
Alkanols	CnH₂n+1OH	-OH	Ethanol
Alkanals	CnH₂nO	-CHO	Ethanal
Alkanones	CnH₂nO	-CO-	Propanone
Alkanoic acids	CnH₂nO₂	-COOH	Ethanoic acid

3. IUPAC Nomenclature

The IUPAC system provides a standardized method of naming organic compounds.

Steps in Naming

• Identify the longest carbon chain.
• Number the chain from the end nearest to the functional group.
• Identify substituents and their positions.
• Use appropriate suffix for the functional group.

Examples

Formula	Name
CH₄	Methane
C₂H₆	Ethane
C₂H₅OH	Ethanol
CH₃CHO	Ethanal
CH₃COOH	Ethanoic Acid

4. Physical Properties of Hydrocarbons

• Generally insoluble in water.
• Soluble in organic solvents.
• Boiling point increases with molecular mass.
• Lower members are gases while higher members are liquids or solids.

5. Chemical Properties of Hydrocarbons

• Combustion: Hydrocarbons burn in oxygen to produce carbon dioxide and water.
• Substitution: Hydrogen atoms may be replaced by other atoms.
• Addition: Unsaturated hydrocarbons add atoms across double bonds.
• Cracking: Large molecules break into smaller molecules.

6. Alkanols (Alcohols)

Alkanols contain the -OH functional group. Example: Ethanol (C₂H₅OH)

Ethanol Structure

CH₃ — CH₂ — OH

Uses

• Fuel
• Solvent
• Antiseptic

7. Alkanals (Aldehydes)

Alkanals contain the -CHO functional group. Example: Ethanal.

CH₃ — CHO

Uses

• Preservatives
• Manufacturing chemicals

8. Alkanones (Ketones)

Alkanones contain a carbonyl group between two carbon atoms. Example: Propanone.

CH₃ — CO — CH₃

Uses

• Solvents
• Industrial chemicals

9. Alkanoic Acids

Alkanoic acids contain the -COOH functional group. Example: Ethanoic acid (vinegar).

CH₃ — COOH

Properties

• Weak acids
• React with metals to produce hydrogen gas
• React with alcohols to form esters

10. Derivatives of Alkanoic Acids

• Esters – formed from alcohols and acids
• Amides – formed with ammonia
• Acid chlorides
• Anhydrides

Example ester formation:

Ethanoic acid + Ethanol → Ethyl ethanoate + Water

SULPHURCBT

Sulphur & H₂SO₄ CBT

Time Remaining: 20:00

Score: 0 / 30

Percentage: 0%

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Theory Questions

1. State two physical properties of sulphur.

Yellow crystalline solid; brittle; insoluble in water.

2. Write the electronic configuration of sulphur.

1s² 2s² 2p⁶ 3s² 3p⁴ (2,8,6).

3. Name the catalyst used in Contact Process.

Vanadium(V) oxide (V₂O₅).

4. Mention two uses of tetraoxosulphate (VI) acid.

Fertilizer manufacture; car batteries; petroleum refining.

5. List the allotropes of sulphur.

Rhombic, Monoclinic and Plastic sulphur.

SULPHURLECTURE

SULPHUR (S)

1. Introduction

Sulphur is a non-metal found in Group 16 (VI A) of the periodic table. Atomic number: 16 Symbol: S Electronic configuration: 2, 8, 6

2. Electronic Structure of Sulphur

Sulphur has 16 electrons arranged as:

1s² 2s² 2p⁶ 3s² 3p⁴

Diagram: Electronic arrangement of Sulphur (2,8,6)

3. Physical Properties of Sulphur

• Yellow crystalline solid
• Brittle and non-metallic
• Insoluble in water
• Soluble in carbon disulphide
• Low melting point

4. Chemical Properties of Sulphur

1. Reaction with Oxygen

S + O₂ → SO₂

2. Reaction with Metals

Fe + S → FeS

3. Reaction with Hydrogen

H₂ + S → H₂S

4. Reaction with Concentrated Acids

Acts as reducing agent.

5. Allotropes of Sulphur

• Rhombic sulphur (α-sulphur)
• Monoclinic sulphur (β-sulphur)
• Plastic sulphur

Diagram: Different allotropes of Sulphur

6. Uses of Sulphur

• Manufacture of tetraoxosulphate (VI) acid
• Vulcanization of rubber
• Manufacture of matches and gunpowder
• Production of fungicides and insecticides

7. Compounds of Sulphur

Compound	Formula	Property
Sulphur dioxide	SO₂	Acidic gas
Sulphur trioxide	SO₃	Reacts with water to form acid
Hydrogen sulphide	H₂S	Rotten egg smell
Tetraoxosulphate (VI) acid	H₂SO₄	Strong acid

8. Industrial Preparation of Tetraoxosulphate (VI) Acid (H₂SO₄)

Prepared by the Contact Process.

Step 1: Burning Sulphur

S + O₂ → SO₂

Step 2: Oxidation

2SO₂ + O₂ ⇌ 2SO₃ (Vanadium(V) oxide catalyst)

Step 3: Absorption

SO₃ + H₂SO₄ → H₂S₂O₇

H₂S₂O₇ + H₂O → 2H₂SO₄

Diagram: Contact Process for H₂SO₄ Production

9. Uses of Tetraoxosulphate (VI) Acid

• Manufacture of fertilizers
• Petroleum refining
• Car batteries (lead-acid batteries)
• Manufacture of detergents and explosives
• Drying agent in laboratory

END OF LECTURE