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Basicity — Strength Order
Typical school: aliphatic amine > NH3 > phenylamine. Explain with availability of the pair. pKb / pKa of conjugate if tables given. Salt formation with HCl gives ammonium chloride — water soluble. This page separates the idea from the wider topic “BASICITY” so it can be revised and assessed on its own.
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Basicity — Strength Order
What is it?
Typical school: aliphatic amine > NH3 > phenylamine. Explain with availability of the pair. pKb / pKa of conjugate if tables given. Salt formation with HCl gives ammonium chloride — water soluble. This page separates the idea from the wider topic “BASICITY” so it can be revised and assessed on its own.
In simple words
- Typical school: aliphatic amine > NH3 > phenylamine.
- Alkyl donors named
- Exam link: pair more available.
Important terms
STRENGTH ORDER: Typical school: aliphatic amine > NH3 > phenylamine.
BASICITY: Amines accept H+ (Bronsted) using the lone pair.
What you should learn
- Define strength order using accurate chemistry terms.
- Explain why strength order matters within basicity.
- Apply the learning unit to an FBISE-style example, comparison, diagram, or calculation.
Examples
- Alkyl donors named
- Ring withdraws named
- Not a dose
KEY IDEA
Typical school: aliphatic amine > NH3 > phenylamine. Explain with availability of the pair. pKb / pKa of conjugate if tables given. Salt formation with HCl gives ammonium chloride — water soluble.
EXAM APPLICATION
Exam basicity: amines are weak bases (lone pair) aliphatic usually > ammonia phenylamine weaker (pair into the ring) if asked
Recommended for Class 11
Full school-level explanation
Typical school: aliphatic amine > NH3 > phenylamine. Explain with availability of the pair. pKb / pKa of conjugate if tables given. Salt formation with HCl gives ammonium chloride — water soluble. This page separates the idea from the wider topic “BASICITY” so it can be revised and assessed on its own.
Study this learning unit in three steps:
WHAT — BASICITY — STRENGTH ORDER
Typical school: aliphatic amine > NH3 > phenylamine. Explain with availability of the pair. pKb / pKa of conjugate if tables given. Salt formation with HCl gives ammonium chloride — water soluble. This page separates the idea from the wider topic “BASICITY” so it can be revised and assessed on its own.
WHY — Why this topic matters
BASICITY — STRENGTH ORDER is an independent FBISE learning unit because students must use its definitions, conditions, equations, or trends separately in explanations and calculations.
HOW — How it works
Typical school: aliphatic amine > NH3 > phenylamine. Explain with availability of the pair. pKb / pKa of conjugate if tables given. Salt formation with HCl gives ammonium chloride — water soluble. Examples: Alkyl donors named; Ring withdraws named; Not a dose. Exam use: Exam basicity: amines are weak bases (lone pair) aliphatic usually > ammonia phenylamine weaker (pair into the ring) if asked
KEY IDEA
Typical school: aliphatic amine > NH3 > phenylamine. Explain with availability of the pair. pKb / pKa of conjugate if tables given. Salt formation with HCl gives ammonium chloride — water soluble.
Remember
- pair more available
Examples
- Alkyl donors named
- Ring withdraws named
- Not a dose
EXAM APPLICATION
Exam basicity: amines are weak bases (lone pair) aliphatic usually > ammonia phenylamine weaker (pair into the ring) if asked
Remember
- pair availability
Examples
- Alkyl donors named
- Ring withdraws named
- Not a dose
Remember
- pair more available
- pair availability
- Federal Board only
- pair more available
- pair availability
- pair more available
- independent learning unit
- pair more available
How the ideas connect
Typical school: aliphatic amine > NH3 > phenylamine. Explain with availability of the pair. pKb / pKa of conjugate if tables given. Salt formation with HCl gives ammonium chloride — water soluble. Examples: Alkyl donors named; Ring withdraws named; Not a dose. Exam use: Exam basicity: amines are weak bases (lone pair) aliphatic usually > ammonia phenylamine weaker (pair into the ring) if asked
Deeper understanding
Go beyond memorising Basicity — Strength Order. Connect the definition to reasons, relationships, exceptions, and exam wording.
How the ideas connect
Typical school: aliphatic amine > NH3 > phenylamine. Explain with availability of the pair. pKb / pKa of conjugate if tables given. Salt formation with HCl gives ammonium chloride — water soluble. Examples: Alkyl donors named; Ring withdraws named; Not a dose. Exam use: Exam basicity: amines are weak bases (lone pair) aliphatic usually > ammonia phenylamine weaker (pair into the ring) if asked
Common mistakes
Exam focus
Core idea
WHAT
WHY
HOW
Exam focus
Quick revision
- pair more available
- pair availability
- Federal Board only
- STRENGTH ORDER: Typical school: aliphatic amine > NH3 > phenylamine.
- BASICITY: Amines accept H+ (Bronsted) using the lone pair.
- WHAT — BASICITY — STRENGTH ORDER: Typical school: aliphatic amine > NH3 > phenylamine. Explain with availability of the pair. pKb / pK
Federal Board Class 11 Chemistry learning unit. Easy wording; no provincial-board material added.
For long answers on Basicity — Strength Order: define clearly → explain the main parts → give one example → state one exam caution.
Exam Focus
Exam Focus
Important points
- pair more available
- pair availability
- Federal Board only
- STRENGTH ORDER: Typical school: aliphatic amine > NH3 > phenylamine.
Important formulas
- pair more available
- pair availability
- Federal Board only
Common exam traps
- Do not treat strength order as the same as every other part of basicity; define this unit and use its own evidence, steps, or conditions.
- Do not memorise a label alone; connect the definition to a process, structure, condition, equation, or example.
Long question structure
Definition → key parts → example → exam caution
Common Mistakes
Common Mistakes
- Mistake
Do not treat strength order as the same as every other part of basicity; define this unit and use its own evidence, steps, or conditions.
- Mistake
Do not memorise a label alone; connect the definition to a process, structure, condition, equation, or example.
- Mistake
Do not use provincial-board wording or add material outside the Federal Board Class 11 scope.
- Mistake
Federal Board Class 11 Chemistry learning unit. Easy wording; no provincial-board material added.
Revision Zone
60-Second Revision
Quick cues from this topic — use them for last-minute revision.
pair more available
pair availability
Federal Board only
STRENGTH ORDER: Typical school: aliphatic amine > NH3 > phenylamine.
Typical school: aliphatic amine > NH3 > phenylamine. Explain with availability of the pair. pKb / pKa of conjugate if tables given. Salt formation with HCl give
- Definition
- Typical school: aliphatic amine > NH3 > phenylamine. Explain with availability of the pair. pKb / pKa of conjugate if tables given. Salt formation with HCl give
- Example
- Alkyl donors named
- Critical warning
- Do not treat strength order as the same as every other part of basicity; define this unit and use its own evidence, step
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Exam Practice
Define
Q1. Define Basicity — Strength Order.
Explain
Q2. Explain: KEY IDEA.
Example
Q3. Give one clear example of Basicity — Strength Order and say why it fits.
Mistake
Q4. State one common mistake students make about Basicity — Strength Order.
Exam note
Q5. Write a short exam note on Basicity — Strength Order: definition, two points, one example.
Sources & References
School-standard facts for Matric and Intermediate. Original explanations — not copied from textbooks.