What type of reaction occurs between silicon dioxide and calcium oxide?

The reaction between silicon dioxide (SiO₂) and calcium oxide (CaO) is classified as a neutralisation reaction because it involves the combination of an acid and a base to form a salt and water. In this case, silicon dioxide acts as an acidic oxide, while calcium oxide is a basic oxide. When these two substances react, they produce calcium silicate, which can be considered a type of salt. This process is characteristic of neutralisation reactions, where an acid and a base interact to neutralize each other.

In contrast to neutralisation, decomposition reactions involve breaking down a compound into simpler substances or elements. Combustion reactions are characterized by the reaction of a substance with oxygen, typically producing heat and light, while reduction reactions involve the gain of electrons or a decrease in oxidation state. None of these alternative types of reactions apply to the interaction between silicon dioxide and calcium oxide, making neutralisation the suitable classification for this specific reaction.