Question

Calgon used as a water softner, is

• A. $Na_2[Na_4(PO_3)_6]$
• B. $Na_4[Na_2(PO_3)_6]$
• C. $Na_4[Na_4(PO_4)_5]$
• D. $Na_4[Na_2(PO_4)_6]$

Answer 1

Answer: (A)

$Na_2[Na_4(PO_3)_6]$

Answer 2

Sodium polymetaphosphate is used to remove the permanent hardness of water. The commercial name of sodium polymetaphosphate is calgon meaning calcium gone. The molecular formula of calgon is $Na_2[Na_4(PO_3)_6].$