Acids contribute to corrosiveness and influence chemical reaction rates, chemical speciation and biological processes. Acidity of water is its quantitative capacity to react with a strong base to a designated pH. The measured value may vary significantly with the end point pH used in the determination.

Apparatus and Reagents

·         Burettes,

·         Pipette

·         Volumetric flask,

·         Conical flask

·          Beaker.

·          Standard sodium hydroxide (0.02N)

·         Phenolphthalein indicator

Procedures

·         Take 100 ml sample in conical flask add 2 drops of Phenolphthalein indicator

·         Titrate with standard NaOH solution till pink colour appears.

·         Record the volume of NaOH solution used

·         Calculate acidity as CaCO3 (mg/l) = ml titrante used (NaOH) x 1000/ ml sample taken

References

1        Sadhana C.; Ananda Dev G.; Handbook of Water, Air and Soil Analysis; a Lab Manual; International-E-Publication;2014

2        Frank R.Spellman; Handbook of water and wastewater treatment plant operations; Lewis publishers;2003

3        Leena Deshpande;Water Quality Analysis Laboratory methods; New Delhi; India.