The residual hardness in ion-exchange process is ____________
A. 0-2 ppm
B. 5-10 ppm
C. 10-15 ppm
D. 20-30 ppm
Answer:A
The residual hardness in ion-exchange process is ____________
A. 0-2 ppm B. 5-10 ppm C. 10-15 ppm D. 20-30 ppm
Explanation: The residual hardness in the ion-exchange process is 0-2 ppm. In