Caustic Soda For Unblocking Toilet ~upd~

High-concentration NaOH (pH >13.5) slowly attacks the silica-based glaze: SiO₂ (glaze) + 2 NaOH → Na₂SiO₃ (sodium silicate, soluble) + H₂O Prolonged or repeated use etches the glaze, making the surface rougher and more prone to future bacterial adhesion and staining.

| Feature | Chemical/Physical Basis | Practical Implication | |---------|------------------------|-----------------------| | Exothermic saponification | Ester bond cleavage + high heat of solution | Melts/dissolves fats but risks thermal shock | | Alkaline protein hydrolysis | Cleavage of disulfide & amide bonds | Dissolves hair completely (unlike acids) | | Density-driven bottom penetration | Solid density > water | Concentrated attack from below blockage | | Incompatibility with mineral scale | No reaction with Ca salts | Cannot fix limescale blockages | | Glaze corrosion | Silica + OH⁻ → silicate | Long-term surface roughening | caustic soda for unblocking toilet