Headings Water Search Questions 
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Methods used to Soften Water.
Apart from boiling, hardness can be
removed from water by using
washing soda or an ion exchange column
in a water softener.
Washing
soda is sodium carbonate.
Adding sodium carbonate to hard
water
will precipitate insoluble calcium carbonate or magnesium carbonate.
This is a way of removing permanent hardness
from water.
Ion exchange
columns.
A water
softener uses an ion
exchange column.
An ion exchange
column is a glass tube filled
with a resin.
Calcium (or magnesium) ions
become exchanged for sodium ions
as water flows through the
column.
Eventually, the column becomes saturated in calcium
ions
and stops being
effective.
The column can be regenerated
by pouring sodium chloride solution (salt
water) through it.
The calcium ions are flushed out and replaced with sodium
ions,
allowing the column to be reused.
For more information about how a
water softener works
please click here. A
water softener is different from a
scale inhibitor.
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