Group 13 Elements: The Boron Family
Chapter Name : The P- Block Elements |
Sub Topic Code : 102_11_11_02_03 |
Topic Name : Group 13 Elements: The Boron Family |
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Sub Topic Name : Ionization Enthalpy |
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Introduction
• The ionisation enthalpy does not decrease smoothly down the group. • The decrease from B to Al is due to increase in size. • The observed discontinuity in the ionisation enthalpy values between Al and Ga, and between In and Tl are due to inability of d- and f-electrons, which have low screening effect, to compensate the increase in nuclear charge. • The order of ionisation enthalpies, as expected, is ?iH1
Pre-Requisites:
Elements, periodic table, Group, ionization enthalpy
Activity:
• Group 13 has aluminium, boron which are important industrial elements.
Real Life Question:
What is aluminium used for?
Key Words / FlashCards
| Key Words | Definitions (pref. in our own words) |
|---|---|
| P block elements | Have the last electron in the outermost p orbital. |
Learning aids / Gadgets
| Gadgets | How it can be used |
|---|---|
| Periodic table | Look at Groups 13 in the periodic table. |
Real life uses :
• Aluminium is a metal used to make utensils, aircraft parts. Etc.
Places to visit :
Chemistry lab.
Practical examples around us
| Examples | Explainations |
|---|---|
| Aluminium | Aluminium belongs to the group 13 elements. |
What you learn in Theory:
• The ionisation enthalpy does not decrease smoothly down the group. • The decrease from B to Al is due to increase in size. • The observed discontinuity in the ionisation enthalpy values between Al and Ga, and between In and Tl are due to inability of d- and f-electrons, which have low screening effect, to compensate the increase in nuclear charge. • The order of ionisation enthalpies, as expected, is ?iH1
What you learn in Practice:
• Group 13 has aluminium, boron which are important industrial elements.