Abstract Blocked drains are a common domestic issue, often leading to the use of harsh chemical unblockers. This paper examines the efficacy of bicarbonate of soda (NaHCO₃) as an alternative unblocking agent. When combined with a weak acid such as vinegar (acetic acid, CH₃COOH), the resulting chemical reaction produces carbon dioxide gas, which exerts physical pressure on blockages. The paper concludes that while NaHCO₃ is effective for minor, organic-based clogs and routine maintenance, it is not a universal solution for severe blockages. 1. Introduction Drain blockages typically consist of organic matter such as hair, soap scum (fatty acid salts), grease, and food particles. Conventional chemical drain cleaners rely on strong oxidising agents (e.g., bleach, sulfuric acid) that generate heat and dissolve organic material. However, these are corrosive, environmentally harmful, and dangerous if mishandled. Bicarbonate of soda (baking soda) offers a low-toxicity, inexpensive alternative. 2. Chemical Mechanism of Action 2.1. The Acid-Base Reaction Bicarbonate of soda alone is a weak base (pH ~8.3). When combined with a weak acid (e.g., white vinegar), the following reaction occurs: