Question

Calgon used as water softener is-

Answer 1

Sodium hexametaphosphate is used as Water Softener:-

• Calgon is used for softening hard water.
• Chemically Calgon is a salt of metaphosphoric acid i.e., Sodium hexametaphosphate $\left({\mathrm{Na}}_4\left[{\mathrm{Na}}_2{\left({\mathrm{PO}}_3\right)}_6\right]\right)$.
• It reacts with the impurities present in that hard water such as calcium and magnesium ion form their phosphatic salt and these are precipitated.