Describe the procedures used to determine the alkalinity test on waste water. (9 marks) b) Define the following words as used in carrying out test on waste water. i. Hardness (2 marks) ii. Turbidity (2 marks) iii. Acidity

a) The procedures used to determine the alkalinity test on waste water are as follows:

1. Collection of Sample: The first step is to collect a representative sample of the wastewater. This should be done in a clean, sterilized container to avoid any contamination.

2. Measurement of pH: The next step is to measure the pH of the sample using a pH meter. This gives an initial indication of the alkalinity or acidity of the water.

3. Titration: The sample is then titrated with a standard solution of a strong acid, usually sulfuric acid or hydrochloric acid. The acid is added slowly while continuously stirring the sample.

4. Indicator: A pH indicator, such as phenolphthalein or bromothymol blue, is added to the sample. The indicator changes color when all the alkalinity has been neutralized by the acid.

5. Endpoint Determination: The titration is continued until the color of the sample changes, indicating that all the alkalinity has been neutralized. This point is known as the endpoint.

6. Calculation: The amount of acid used to reach the endpoint is measured and used to calculate the alkalinity of the sample. The result is usually expressed in milligrams per liter (mg/L) of calcium carbonate (CaCO3).

b) Definitions:

i. Hardness: In the context of wastewater testing, hardness refers to the concentration of divalent metal ions, primarily calcium and magnesium, in the water. These ions can form scale in pipes and boilers and interfere with the action of soaps and detergents.

ii. Turbidity: Turbidity is a measure of the cloudiness or haziness of a fluid caused by large numbers of individual particles that are generally invisible to the naked eye. In wastewater, turbidity can be caused by the presence of suspended solids, microorganisms, or other substances.

iii. Acidity: Acidity in wastewater refers to the capacity of the water to neutralize bases, or in other words, the amount of acid substances in the water. It is usually measured by titration with a standard solution of a strong base.