Oxides
Types of oxide
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Acidic oxides — oxides of non-metals (e.g. $\text{SO}_2$, $\text{CO}_2$).
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Basic oxides — oxides of metals (e.g. $\text{CuO}$, $\text{CaO}$).
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Amphoteric oxides react with both acids and bases ($\text{Al}_2\text{O}_3$, $\text{ZnO}$).
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So metal oxides tend to be basic, non-metal oxides tend to be acidic.
Practice
Acidic oxides are usually oxides of:
Non-metal oxides (e.g. CO2, SO2) are acidic; metal oxides are basic.
Practice
An amphoteric oxide such as Al2O3 reacts with:
Amphoteric oxides (Al2O3, ZnO) react with both acids and bases to give a salt and water.
Practice
Classify each oxide.
CO2 (non-metal) acidic, CaO (metal) basic, ZnO amphoteric.
You've got it
Key idea
- non-metal oxides → acidic ($\text{SO}_2$, $\text{CO}_2$)
- metal oxides → basic ($\text{CuO}$, $\text{CaO}$)
- amphoteric oxides react with both acids and bases ($\text{Al}_2\text{O}_3$, $\text{ZnO}$)