Final answer:
The correct answer is option 1.2KClO3 →2KCl+3O2.
Step-by-step explanation:
The reaction that is both a redox and a decomposition reaction is option 1: 2KClO3 → 2KCl + 3O2. This is because potassium chlorate (KClO3) breaks down into potassium chloride (KCl) and oxygen gas (O2), which qualifies it as a decomposition reaction. Additionally, this reaction involves the transfer of electrons, indicating a redox process where the chlorate (ClO3-) is reduced to chloride (Cl-) and the oxygen is oxidized from O- in ClO3- to O2.
As for the concept of a decomposition reaction, it involves the breakdown of a single compound into two or more products. An example of a decomposition reaction is seen in the thermal decomposition of calcium carbonate: CaCO3 → CaO + CO2, where calcium carbonate decomposes into calcium oxide (CaO) and carbon dioxide (CO2).
In redox reactions, there's a transfer of electrons between the reacting species which changes the oxidation states of the elements involved. For example, in the combustion of methane: CH4 + 2O2 → CO2 + 2H2O, carbon is oxidized and oxygen is reduced.