This was necessary to provide a true basis of comparison as some turbidity removal could have taken place without coagulant addition. If a color test were conducted on the filtrate collected after filtering out suspended solids, the type of color being measured would be true color apparent color. If a color test were conducted on an unfiltered sample, the type of color measured would be true color apparent color. Alum coagulation can remove apparent color but not true color. Alum coagulation can remove true color but not apparent color.
Alum coagulation can remove neither true color nor apparent color.
Alum coagulation can remove both true color and apparent color. When you press the submit button your answers will be recorded for grading. The answers will then be echoed back to your computer. Copyright 2001 . All rights reserved.