Define the Octet rule. Give two examples of such compounds in which an exception to the Octet rule is observed.
OR
Write two important differences between ionic and covalent compounds.
WBBSE
Class X
Physical Science
Ionic and Covalent Bond
02 Mark
2024
Octet Rule: Atoms tend to gain, lose, or share electrons to achieve 8 electrons in their outer shell.
Exceptions:
- BeCl2: Beryllium has 4 electrons in its outer shell.
- BF3: Boron has 6 electrons in its outer shell.
OR
The differences between ionic and covalent compounds:
| Property | Ionic Compounds | Covalent Compounds |
|---|---|---|
| Bond Type | Transfer of electrons | Sharing of electrons |
| Melting/Boiling Points | High melting/boiling points | Lower melting/boiling points |
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