Addition reactions are typically characterized by

• A. A single product formed
• B. Two products formed
• C. A mixture of products
• D. No product formed

Answer: (A)

Addition reactions attach two atoms or groups across a carbon–carbon multiple bond, converting an unsaturated molecule into a saturated one. Because the two new bonds form across the same bond and there’s typically one way the reagents can add under standard conditions, you end up with a single main product. For example, hydrogen adding to an alkene produces one saturated hydrocarbon, and halogen addition across the double bond yields one vicinal dihalide. While in some cases there can be variations (regio- or stereochemical outcomes) in specific situations, the usual outcome described here is a single product.