Final answer:
A combination reaction involves the formation of a single product from two or more substances. A decomposition reaction involves the breakdown of a single compound into simpler substances. Replacement reactions involve the swapping of elements in compounds.
Step-by-step explanation:
A combination reaction occurs when two or more substances react to form a single product. This can be represented by the general equation: A + B → AB. An example of a combination reaction is the formation of water from hydrogen and oxygen: 2H2 + O2 → 2H2O.
A decomposition reaction is the opposite of a combination reaction. It occurs when a single compound breaks down into two or more simpler substances. The general equation for a decomposition reaction is: AB → A + B. An example is the decomposition of hydrogen peroxide into water and oxygen: 2H2O2 → 2H2O + O2.
A replacement reaction, also known as a displacement reaction, involves swapping one element in a compound with another element. There are two types of replacement reactions: single replacement and double replacement. In a single replacement reaction, an element reacts with a compound to form a new compound and release a different element. For example, the reaction between iron and copper sulfate can be represented as: Fe + CuSO4 → FeSO4 + Cu. In a double replacement reaction, two compounds exchange elements to form new compounds. An example is the reaction between silver nitrate and sodium chloride: AgNO3 + NaCl → AgCl + NaNO3.