Agriculture & soil science.

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Determination of calcium from irrigation water sample.

Aim - Determination of Calcium from irrigation water sample. Principle - When disodium salt of is added to water containing both calcium + magnesium is a determine separately with calcon indicator with 10% solution. Sodium EDTA forms a stronger Complex with calcium the the solution changes from Pink to blue colour. Record the volume of standard edit for calculating calcium in water. Reagents - 1) EDTA SOLUTION (0.01N) - Weigh 2 gram versenate (disodium hydrogen EDTA) dissolve it in distilled water make up volume 1 litre. 2) Sodium hydroxide (10%) - 10 gram is NaoH dissolved in distilled water and make the volume hundred ml. 3) Calcon indicator - Dissolve 20 ml gram of calcon in 50 ml of methanol (or ethanol). 4) Potassium ferrocyanide (K4fe(cn)6) - Dissolve 4 gm potassium ferrocyanide in hundred ml distilled water. 5) Hydroxylamine hydrochoride (NH4oH. Hcl) - Dissolved 5 gram hydroxylamine hydrochloride in hundred ml distilled water. 6) Triethanolamine - TEA indicator reagent gr

Determination of sodium from irrigation water sample.

Aim Determination of sodium from irrigation water sample. Principle Small amount of sodium are generally present in the best quality of irrigation water. Sodium constitutes about 50% or more of total cations of saline and sodic water. The content of sodium maybe quite Hagi in saline water and containing relatively less amount of calcium and magnesium at Higher level of sodium it also exerts a toxic effect on the plant growth. Therfore determination of sodium in irrigation water is very important for predicting for the harmful effect On soil and crops and judging the suitability of water for irrigation. The Determination Sodium Potassium is carried out directly with help of flame photometer using appropriate filter and standard curve prepared by taking known concentration of sodium. Reagents - 1) Std. Sodium solutions (stock solution) - Dissolve 5.845 gram of sodium chloride(AR) in distilled water and make up the volume with 1 litre with distilled water. This gives hundred Milli

Determination of SULPHATE from irrigation water sample.

Aim - Determination of Sulphate from irrigation water. Principle Sulphate iron are precipitate as Barium sulphate crystal of uniform size in acidic medium. Method Terbidimetric method. Reagents 1) Barium chloride ( Bacl2 . 2 H2O crystal of 20-30) 2) conditioning reagent - Dissolve 75 gram sodium chloride in 300 ml distilled water. Add 30 ml of concentrated HCL and hundred ml 95% ethyl alcohol (or isopropyl alcohol ) and 50 ml of glycerol and mix well and makeup volume to 500ml distilled water. 3) standard sulphate solution - Dissolved 0.1479 gram of unhydrous sodium sulphate In distilled water and make up to 1000ml. This gives 100 microgram per ml (PPM) solution of sulphate. Procedure Take hundred ml water sample into 250 Ml conical flask. Add 5 ml conditioning reagent and mix well using magnetic stirrer. The speed of stirring should be same for both sample and standard. While stirring add about 0.5 gram Barium Chloride crystal all at once and continued to sti

Determination of CLORIDES from irrigation water sample.

Aim - Determination of chloride from irrigation water simple. Principle - Mohr's titration method (argentrometric) is most commonly used for chlorides determination. It Depend upon formation of sparingly soluble greek silver chromate (AgcrO4) precipitated at the end point. When sample is titrated against the standard Silver Nitrate (AgNo3) solution in presence of potassium chromate (k2crO4) as colour indicator. Reagents - 1) potassium chromate indicator 5% solution - Dissolved 5gm potassium chromate in about 75 distilled water and add saturated solution of silver nitrate. Dropwise until a slite permanent red precipitated is formed. Filter and dilute 100ml with distilled water . 2) standard silver nitrate (0.02 normality AgNo3) - Dissolved 3.40 gram silver nitrate in distilled water and volume made up to 1 litre and stored in Amber colour bottle away from light. Procedure - Take 10 ml of water sample in hundred ml conical flask and dilute to 25 ml with distilled water. Add 5 dr

Determination of carbonates and bicarbonates from irrigation water sample.

Aim - Determination of carbonates and bicarbonates from irrigation water sample. In irrigation water important ions namely chloride, sulphates, nitrates, carbonates and bicarbonates are present . some of the carbonates and bicarbonates ions constituted the total alkalinity of water. Principle - The Carbonate and Bicarbonate ions in the sample can be determined by titrating it against standard sulphuric acid using phenolphthalein and methyl orange indicator respectively . addition of phenolphthalein gives pink red colour in presence of carbonates and titration with H2So4 converts this carbonates into bicarbonates and decolourise the pink red colour of the solution. In colourless solution methyl orange is added with gives yellow colour to the solution further titration against H2 s o4 neutralization of all bicarbonates and colour of solution changes from yellow to red orange. Reagents - 1 ) standard sulphuric acid (0.01 normality) - Take 0.28 ml H2 s o4 (36 normality) with atomic

Determination of pH and E. C. From irrigation water sample

Title. - Determination of PH and electrical conductivity from irrigation water sample Determination of PH.- The pH value is the negative normal logarithmic of the hydrogen ion activity. As a result of presence of strong bases increase PH value and presence of strong acid cause decrease in pH value. The pH value of neutral water usually lie between 6.5 to 7.5 . lower value of PH results of free carbonates #decalcification in surface water can increase PH value upto 9.5 Apparatus . - PH metre with glass calomel electrode assembly. Regent. Buffer solution of PH 4, 7, 9.2 Procedure.- Take 50 ml water sample in hundred ml beaker . Determine pH of water. Before measurement of pH of sample standardise the pH metre using standard buffer solution. Result ------- PH ratings - <6.5. Acidic 6.5 to 7.5. Neutral >7.5. Basic /alkali. Determination of electrical conductivity. - Electrical conductivity is the measure of water capacity to carry electric cur