Seminar project

1,391 views

Published on

HARDNESS OF WATER AND ITS DETERMINATION

Published in: Business, Technology
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total views
1,391
On SlideShare
0
From Embeds
0
Number of Embeds
2
Actions
Shares
0
Downloads
25
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide

Seminar project

  1. 1. PRESENTATION ON “HARDNESS OF WATER & ITS DETERMINATION”
  2. 2. ACKNOWEDGEMENT I owe a great many thanks to a great many people who helped and supported me during the writing of this assignment. My deepest thanks to lecturer, the guide of the project, for guiding and correcting various documents of mine with attention and care. I would also thanks my institution and my faculty members without whom this project would have been a distant reality. I also extend my heartfelt thanks to my family and well wishers.
  3. 3. Constituents- 2 elements of H2 1 element of O2 3 states of water- Solid, Liquid & Gas Occurrence- Most abundant & widely distributed 3/4th of Earth’s crust
  4. 4. STRUCTURE • H20 is Polar i.e. ,it is partially charged • O2 has higher Electronegativity • H2O is a solvent • Forms 104.5deg angle • Bent shape/V-shape structure • H-bonding
  5. 5. HARDNESS OF WATER Soap consuming power of water is called Hardness. Ca2+/Mg2+ cationsCause Hardness SoapSodium/Potassium salts of oleic acid, palmitic acid, stearic acid. 2C17H35COONa + CaCl2  (C17H35COO)2Ca +2NaCl (Sodium stearate) 2C17H35COONa + Ca(HCO3)2 (C17H35COO)2Ca + 2NaHCO3 Calcium stearate (Insoluble salt)
  6. 6.  There are two types of hardness-  Temporary hardness  Permanent hardness 1>Temporary hardness- ~it is due to the presence of soluble salts of HCO3- of Ca & Mg. ~it can be removed by boiling. In this the HCO3- are decomposed into insoluble CO32- Ca(HCO3)2CaCO3 + H2O + CO2 (soluble) (insoluble)
  7. 7.  2. Permanent hardness It is due to sulphides,chlorides & nitrates of calcium, magnesium & other metals. CLASSIFICATION OF HARDNESS Alkaline hardness Non-alkaline hardness carbonates,bicarbonates chlorides,sulphides &. & hydroxides of metals nitrates of metals
  8. 8.  1.SOAP SOLUTION METHOD: Ca(HCO3)2+2C17H35COONa(C17H35COO)2Ca +NaHCO3 Ca bicarbonate sodium stearate Ca stearate CaCl2 +2C17H35COONa(C17H35COO)2Ca+2NaCl CaSO4+2C17H35COONa(C17H35COO)2Ca+Na2SO4
  9. 9.  Hardness causing metal ions get precipitated.  When more sodium salt is added, lather is formed.  The aliquot is titrated against standard soap solution in alcohol.  End point indicates total hardness.  The aliquot is boiled for 30 mins.  Temporary hardness get removed(may be due to the formation of CO2 which escapes)
  10. 10.  2.EDTA method: Burette:Na2[EDTA]H2[EDTA]H2 2- +2Na+ Flask:Ca2+/Mg2++[EBT]H[EBT]Ca +H+ (blue) (wine red) Titration: [EDTA]H2 2-+[EBT]Ca[EDTA]Ca+[EBT]H {end point} (wine red) colorless blue
  11. 11.  Boil the aliquot for 30mins  Temporary hardness is removed  The remaining again titrated against Na2[EDTA]H2 complex  End point indicates permanent hardness {Total hardness-Permanent hardness=temporary hardness}
  12. 12.  Blockage of passage occurs when water is used for cooling due to scale deposition.  Hard water is harmful for drinking as it causes deposition of calcium in the bone joints.  It causes formation in boilers and pipes.  Hard water does not form any lather with soaps or detergents.
  13. 13.  Hard water is calculated in terms of calcium carbonate. It is because of the following reasons:  Molecular weight of CaCO3 is: 40+12+16x3=100  Most insoluble salt of Ca which is precipitated during water treatment processes.  Equivalent of CaCO3 = =[Mass of hardness producing substance x chemical equivalent of CaCO3 Chemical equivalent of hardness producing substance = [Mass of hardness producing substance in mg/L]x multiplication factor

×