How can I tell what type of reaction it is just by looking at the equation? I always get confused between decomposition and displacement.

Identifying reaction types involves observing the number of reactants and products, and how they interact.

• Combination Reaction: Two or more reactants combine to form a single product (e.g., $A + B \rightarrow AB$). Look for multiple substances forming just one.
• Decomposition Reaction: A single reactant breaks down into two or more simpler products (e.g., $AB \rightarrow A + B$). This is the opposite of combination; look for one substance breaking apart.
• Displacement Reaction: A more reactive element displaces a less reactive element from its compound (e.g., $A + BC \rightarrow AC + B$). Here, an element 'kicks out' another element from a compound.
• Double Displacement Reaction: Two compounds exchange their ions to form two new compounds (e.g., $AB + CD \rightarrow AD + CB$). Look for two compounds reacting and two new compounds forming, often resulting in a precipitate, gas, or water.
• Redox Reaction: Involves the transfer of electrons (oxidation and reduction occurring simultaneously). While all combination, decomposition, and displacement reactions are redox, double displacement usually isn't. Focus on the number and nature of reactants and products to distinguish.