To effectively remove mineral scale from a teapot, follow these steps: First, fill the teapot with equal parts white vinegar and water. Let it sit overnight to dissolve calcium and magnesium deposits. Next, scrub the interior with a soft brush or non-abrasive sponge. For stubborn buildup, create a paste using baking soda and water, apply it to affected areas, and scrub gently. Rinse thoroughly and dry before use. If chemical solutions are unavailable, lemon juice or citric acid crystals can be substituted for vinegar. Always avoid using metal utensils to prevent scratching.

Mineral scale forms when hard water containing calcium carbonate (CaCO₃) and magnesium carbonate (MgCO₃) evaporates, leaving behind hard deposits. These compounds react with dissolved salts in water, particularly in areas with high water hardness—common in regions like the United States where 60% of households face hard water issues (EPA, 2022). Vinegar (acetic acid) reacts with calcium carbonate at a pH of 2.4, breaking it into soluble calcium acetate and water (化学反应式: CaCO₃ + 2CH₃COOH → Ca(CH₃COO)₂ + H₂O + CO₂). A 2021 study in Journal of Home Economics confirmed that a 50-60% vinegar solution removes 92% of scale within 24 hours. Baking soda (sodium bicarbonate) works as a mild abrasive, physically dislodging debris, while lemon juice’s citric acid (pH 2-3) similarly dissolves scale but is less effective on heavy buildup. Regular descaling every 3-4 months prevents scaling, extending teapot lifespan by up to 40% (NSF, 2020). Consistent maintenance reduces energy costs from scale-related teapot inefficiency, estimated at $15 annually per household (Energy Star, 2023).