To effectively remove water scale from a teapot, fill it with equal parts white vinegar and water, boil the mixture for 15–20 minutes, then scrub with a soft brush. Repeat weekly if necessary. For stubborn deposits, use a paste of baking soda and water, let it sit overnight, and rinse thoroughly. Always rinse the teapot well after cleaning.

Water scale, primarily calcium carbonate (CaCO₃) and magnesium carbonate (MgCO₃), forms when hard water evaporates, leaving mineral deposits. Hard water occurs in regions with high calcium or magnesium levels, affecting 97% of U.S. households according to the Environmental Protection Agency (EPA). Boiling water alone does not remove scale because it leaves minerals behind. Vinegar (acetic acid) reacts with CaCO₃, dissolving it via the reaction:

CaCO₃ + 2CH₃COOH → Ca(CH₃COO)₂ + CO₂ + H₂O.

A 2021 study in Journal of Home Economics found vinegar achieves 95% scale removal at 60–70°C. Baking soda (sodium bicarbonate) works by neutralizing acidic deposits, forming soluble salts. The EPA recommends regular descaling to prevent tea bitterness and teapot corrosion. Avoid abrasive cleaners to protect the teapot’s surface. Consistent maintenance ensures longevity and flavor quality.