hardness of water

1. WHAT IS HARDNESS OF
WATER ?

2. TOPICS
• WHAT IS HARDNESS OF WATER?
• REACTION OF SOAP WITH WATER
• HARD WATER VS SOFT WATER –COMPARISON
• TYPES OF WATER HARDNESS & REMOVAL METHOD
• DETERMINATION OF HARDNESS
• HARDNESS UNITS & CONVERSION TABLE

3. WHAT IS HARDNESS OF WATER?
AS PER CHEMISTRY, THE AMOUNT OF CALCIUM & MAGNESIUM IONS PRESENT IN
WATER.
IN OTHER WORDS HARDNESS OF WATER MEANS THE LATHER PRODUCING
CAPACITY OF WATER.
HARD WATER CONTAINS MORE CALCIUM & MAGNESIUM IONS & PRODUCES LESS
LATHER WITH SOAP
SOFT WATER CONTAINS LESS CALCIUM & MAGNESIUM IONS & PRODUCES MORE
LATHER WITH SOAP

4. REACTION OF SOAP WITH WATER
• SOAP CONTAINS LONG CHAIN FATTY ACIDS OF SODIUM SALT.WHEN SOAP
REACT WITH WATER CALCIUM & MAGNESIUM IONS PRESENT IN WATER IS
CONVERTED TO CORRESPONDING CALCIUM & MAGNESIUM SALTS & IT IS
PRECIPITATE AS SCUM. THIS SCUM IS STICKS ON THE SURFACE TO BE CLEANED
SO THAT CLEANING CAPACITY OF SOAP IS REDUCED

5. HARD WATER VS SOFT WATER
HARD WATER
• MORE CALCIUM & MAGNESIUM IONS
ARE PRESENT
• PRODUCES LESS LATHER WITH SOAP
• TOTAL HARDNESS VALUE IS >60PPM
AS CACO3
SOFTWATER
• LESS CALCIUM & MAGNESIUM IONS
ARE PRESENT
• PRODUCES MORE LATHER WITH SOAP
• TOTAL HARDNESS VALUE IS < 60PPM
AS CACO3

7. CARBONATE HARDNESS OR TEMPORARY
HARDNESS
• HARDNESS PRESENT IN WATER IS DUE TO CARBONATE(CO3) & BICARBONATE(HCO3)
IONS IS CALLED CARBONATE OR TEMPORARY HARDNESS OF WATER
• IT IS CALLED TEMPORARY HARDNESS BECAUSE IT IS REMOVED WHEN WE BOIL THE
WATER

8. NON-CARBONATE HARDNESS OR PERMANENT
HARDNESS
• HARDNESS PRESENT IN WATER IS DUE TO CHLORIDE(CI) &SULFATE(SO 4) IONS IS
CALLED NON-CARBONATE OR PERMANENT HARDNESS OF WATER IT IS CALLED
PERMANENT HARDNESS OF WATER
• IT IS CALLED PERMANENT HARDNESS BECAUSE IT IS NOT REMOVED WHEN WE
BOIL THE WATER
• IT IS REMOVED BY SOFTENING OR DEMINERALIZATION PROCESS

9. WATER HARDNESS ANALYSIS
OVERVIEW
Calcium
hardness
Magnesium
hardness
Total
hardness

10. DETERMINATION OF TOTAL HARDNESS

11. DETERMINATION OF CALCIUM HARDNESS

12. DETERMINATION OF MAGNESIUM HARDNESS
• MAGNESIUNM HARDNESS IS DETERMINED BY
SUBTRACTING CALCIUM HARDNESS VALUE FROM TOTAL
HARDNESS
CALCULATION:
MAGNESIUM HARDNESS=TOTAL HARDNESS-CALCIUM
HARDNESS PPM AS CACO3

13. WATER HARDNESS CLASSIFICATION

14. WATER HARDNESS UNIT CONVERSION