Explain all the types of the …

In chemistry, reactions are classified into different types based on the nature of reactants, products, and the way they react. Here are the most common types of chemical reactions: Combination or Synthesis Reaction: A combination reaction is when two or more substances combine to form a single new substance. For example, when hydrogen gas (H2) combines with oxygen gas (O2), they form water (H2O). The general equation for this type of reaction is A + B → AB. Decomposition Reaction: A decomposition reaction is the opposite of a combination reaction. In this type of reaction, a single substance breaks down into two or more simpler substances. For example, when water (H2O) is heated, it breaks down into hydrogen gas (H2) and oxygen gas (O2). The general equation for this type of reaction is AB → A + B. Single Replacement or Displacement Reaction: In a single replacement reaction, one element replaces another in a compound. For example, when zinc (Zn) metal is added to hydrochloric acid (HCl), it replaces hydrogen (H) in the acid to form zinc chloride (ZnCl2) and hydrogen gas (H2). The general equation for this type of reaction is A + BC → AC + B. Double Replacement or Displacement Reaction: In a double replacement reaction, two ionic compounds react and exchange ions to form two new compounds. For example, when sodium chloride (NaCl) is mixed with silver nitrate (AgNO3), they exchange ions to form sodium nitrate (NaNO3) and silver chloride (AgCl). The general equation for this type of reaction is AB + CD → AD + CB. Combustion Reaction: A combustion reaction is a type of reaction that involves the reaction of a substance with oxygen gas (O2), usually with the release of heat and light. For example, when methane (CH4) gas is burned in the presence of oxygen, it produces carbon dioxide (CO2) and water (H2O) vapor. The general equation for this type of reaction is fuel + O2 → CO2 + H2O + heat. These are the most common types of chemical reactions that you will encounter in your chemistry studies.