Study the relationship of chemicals in the environment. Understand why some areas of the country have restricted the use of detergents that contain "non-biodegradable" phosphates. The presence of phosphate is indicated when the water sample turns blue.10 calibrated sample tubes with caps 2 drop-controlled bottles, phosphate solutions #1 2 drop-controlled bottles, phosphate solutons #2 10 student worksheets and quides Instruction manual with MSDS