Metal oxides decompose, typically when heated, into their constituent elements: the metal and oxygen gas.
The decomposition process depends on the metal's reactivity. Highly reactive metals like sodium form stable oxides that require significant energy (high temperatures) to decompose. Less reactive metals have oxides that decompose more readily.
Here's a breakdown:
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General Reaction: Metal Oxide (MO) → Metal (M) + Oxygen (O₂)
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Example from the provided text: Sodium Oxide (Na₂O) → Sodium (Na) + Oxygen (O₂)
Factors Affecting Decomposition:
- Metal Reactivity: More reactive metals form more stable oxides. Stability means more energy (usually heat) is required to break the bonds and cause decomposition.
- Temperature: Higher temperatures generally favor decomposition.
- Catalysts: The presence of a catalyst can lower the activation energy required for decomposition, allowing it to occur at lower temperatures.
Decomposition of Sodium Oxide (Na₂O)
As the video clip mentions, sodium oxide decomposes into sodium metal and oxygen gas:
2Na₂O(s) → 4Na(s) + O₂(g)
This requires a significant amount of energy due to sodium's high reactivity.
In summary, metal oxide decomposition is a chemical process where a metal oxide breaks down into its elemental metal and oxygen, usually driven by heat, with the ease of decomposition dependent on the metal's reactivity and other factors.
