The reagent(s) used for softening the temporary hardness of water area) Ca3(PO4)2 b) Ca(OH)2c) Na2CO3d) NaOCl

Temporary hardness of water is due to the presence of soluble bicarbonates of Ca & Mgi.e,. Ca(HCO3)2   Ag(HCO3)2The temporary hardness of water is removed by 3-ways in all these 3-Process soluble bicarbonates converting into insoluble  carbonates(1) By boiling(2) By heating  with washing soda  [Na2CO3.10H2O] (3) By clark's process: Reagent used in this process is Ca(OH)2.