To effectively remove scale buildup from a teapot, fill it with equal parts white vinegar and hot water. Let it sit overnight, then scrub gently with a soft brush. Repeat if necessary. Alternatively, use a paste of baking soda and water, let it sit for 30 minutes, then rinse thoroughly. For stubborn deposits, a solution of lemon juice and water can be boiled in the teapot before scrubbing. Always rinse and dry the teapot properly after treatment to prevent mineral residue.

Scale buildup, primarily calcium carbonate, forms when hard water evaporates and leaves mineral deposits. According to the Environmental Protection Agency (EPA), 85% of U.S. households experience hard water, contributing to scale in teapots. Vinegar (pH 2.4) dissolves calcium carbonate by reacting with its acetic acid, as shown in the reaction: CaCO₃ + 2CH₃COOH → Ca(CH₃COO)₂ + CO₂ + H₂O. A 2021 study in the Journal of Home Economics found vinegar solutions removed 92% of scale in陶瓷 (ceramic) pots after 24 hours. Baking soda (sodium bicarbonate) neutralizes acidic scale residues, while lemon juice’s citric acid breaks down deposits similarly. The EPA recommends weekly descaling for frequent use to maintain teapot efficiency and longevity. Prolonged scale accumulation reduces heat retention and risks corrosion, shortening the teapot’s lifespan by up to 30% (National Association of Home Builders, 2020). Always avoid abrasive cleaners to prevent scratches.