Which of these chemicals is added in the post anoxic step?

A sludge blanket in the reactor is __

For which of the following activated carbon is not used?

TDS decreases the efficiency of hot water heaters.

______ is the value of the sieve opening through which exactly 50 % of the resin volume passes.

________ is used in detergents to soften water.

The filter once installed need not to be replaced in activated carbon filtration.

The cathode material corrodes during the process.