Copper+oxygen=copper oxide.
And it is categorised in the category of combination reaction.

So, answer (c)is correct.

Combination reaction

- A combination reaction is a type of chemical reaction in which two or more substances combine to form a single product. In this reaction, the reactants lose their individual properties and form a new substance with different properties.
- The chemical reaction between copper and oxygen falls under the category of a combination reaction because copper reacts with oxygen to form copper oxide (CuO).
- The reaction can be represented by the following balanced chemical equation:
2Cu + O2 → 2CuO

Explanation:

Copper and oxygen react with each other to form copper oxide. Here is a step-by-step explanation of the reaction:

1. Copper (Cu) is a metal that readily reacts with oxygen (O2) present in the air.
2. When copper is exposed to oxygen, it undergoes a chemical reaction where the copper atoms combine with the oxygen molecules.
3. The copper atoms lose electrons and become positively charged ions (Cu2+), while the oxygen molecules gain electrons and become negatively charged ions (O2-).
4. The positively charged copper ions and negatively charged oxygen ions attract each other and form a compound called copper oxide (CuO).
5. The copper oxide formed has different properties than the individual copper and oxygen.
6. The reaction is exothermic, meaning it releases energy in the form of heat.

Significance:

The reaction between copper and oxygen is significant in various applications:

1. Corrosion: When copper is exposed to air and moisture, it gradually forms a layer of copper oxide on its surface, which protects the underlying copper from further corrosion.
2. Catalysts: Copper oxide is used as a catalyst in various chemical reactions, such as the oxidation of carbon monoxide to carbon dioxide.
3. Pigments: Copper oxide is used as a green pigment in ceramics, paints, and dyes.
4. Electrical conductivity: Copper is an excellent conductor of electricity, and the formation of copper oxide does not significantly affect its conductivity.

In conclusion, the chemical reaction between copper and oxygen is categorized as a combination reaction because copper and oxygen combine to form copper oxide.