Grade 12 Physical Sciences · Matter and Materials

Define organic chemistry terms

Give the exact meaning of organic chemistry words like hydrocarbon, functional group, homologous series and saturated compound.

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Introduction to Organic Chemistry Gr 12Kevinmathscience

Grade 12 Organic Chemistry Introduction: Physical SciencesMiss Martins Maths and Science

Grade 12 Organic Chemistry Homologous series part 1Miss Martins Maths and Science

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Question 2.1 · May/June 2025 · Paper 2 · National (DBE) · 2 marks

The letters A to F in the table below represent organic compounds. Diagram for this question

2.1 Define the term unsaturated compound.(2)

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3. Question 4.2.1 · November 2025 · Paper 2 · National (DBE) · 2 marks
4.2 A compound with the formula $C_{10} H_{22}$ undergoes a cracking reaction according to the equation:

$C_{10} H_{22} (ℓ) \to 2 X(g) + C_{4} H_{10} (g)$

The mixture of the two products is bubbled in bromine water, $Br_{2}$ (aq), in a darkened room.

Answer the questions that follow.
4.2.1 Define the term cracking.(2)
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  Definition of crackingThe chemical process/reaction in which longer chain hydrocarbon/alkane molecules are broken down to shorter (more useful) molecules.
  2 marks · Define organic chemistry terms
4. Question 3.1.1 · May/June 2025 · Paper 2 · National (DBE) · 2 marks
3.1 The boiling points of straight chain aldehydes and straight chain carboxylic acids are compared. The table below shows the results obtained.

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3.1.1 Define the term homologous series.(2)
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  Definition of homologous series(A series of organic) compounds that can be described by the same general formula.
  2 marks · Define organic chemistry terms
5. Question 2.3.1 · November 2024 · Paper 2 · National (DBE) · 2 marks
The letters A to H in the table below represent organic compounds.
2.3 Two different compounds in the above table are functional isomers.
2.3.1 Define the term functional isomer.(2)
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  Same molecular formulaCompounds with the same molecular formula,
  1 mark · Define organic chemistry terms
2. ✓
  Different functional groups/homologous seriesbut different functional groups/homologous series.
  1 mark · Define organic chemistry terms
6. Question 2.1 · May/June 2024 · Paper 2 · National (DBE) · 2 marks
The letters A to H in the table below represent eight organic compounds.
2.1 Define the term hydrocarbon.(2)
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1. ✓
  Definition of a hydrocarbonOrganic compounds that consist of hydrogen and carbon only.
  2 marks · Define organic chemistry terms

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