CWEA LABORATORY ANALYST EXAM ALL GRADES 2026/2027 TEST BANK | ACCURATE REAL EXAM VERSIONS | CURRENTLY TESTING WITH A STUDY GUIDE

CWEA LABORATORY ANALYST EXAM ALL GRADES 2026/2027 TEST BANK | ACCURATE REAL EXAM VERSIONS | CURRENTLY TESTING WITH A STUDY GUIDE Chloride - Major anion found in many natural waters - Can impart salty taste in H2O What increases concentration of chloride in wastewater Chloride in human diet and softeners flushed into sanitary sewer system 2 most prevalent methods of measuring chloride argentometric and mercuric nitrate Argentometric Titration of sample with standard solution of silver nitrate (AgNO3) - Indicator: Chromate ions (CrO4) - End point: reddish silver chromate Mercuric Nitrate Titration with standard mercuric nitrate solution -pH must be adjusted between 2.3 and 2.8 - Indicator: Diphenyl carbazone - End point: Change from blue to purple in presence of mercury Interference of Mercuric Nitrate Method Sulfide, bromide, orthophosphate (over 30 ppm), and iodide Why does color change in water Presence of decaying vegetable matter, metal ions (ie. iron) or industrial and domestic pollution How is color measured Measured using visual comparison method Visual comparison method Sample compared to standards using matched nessler tubes - Standards prepared with solution containing cholorplatinate and cobaltous chloride Standard units for color One unit= color resulting from 1 mg of platinum/L 2 color reporting True and Apparent True color Color from dissolved substances, determine using sample treated to remove turbidity