Which of the following statements concerning the hardness of water and the methods used for its remo — Hydrogen Chemistry Question

💡 Solution & Explanation

Temporary hardness is due to bicarbonates and can be removed by boiling or Clark's method (lime). Permanent hardness (due to chlorides/sulfates) cannot be removed by boiling. Calgon ($Na_6P_6O_{18}$) removes hardness by sequestering the $Ca^{2+}/Mg^{2+}$ ions into soluble complexes, preventing them from reacting with soap.