California Water Treatment Operator Exam, Laboratory Procedures: all 26 questions
All questions from the Laboratory Procedures section for California Water Treatment Operator Exam, each with the correct answer.
- 4001Which container is required for a routine bacteriological (coliform) sample?
- 4002Why is the sample tap flame-sterilized or disinfected before collecting a bacteriological sample?
- 4003Chain of custody documentation for a sample records
- 4005Free chlorine in a water sample is most often measured in the field with
- 4006A DPD chlorine test must be run immediately after sampling because
- 4007The difference between total chlorine and free chlorine is the
- 4008A colorimeter measures the concentration of a substance by
- 4009The pH scale measures
- 4010A water sample with a pH of 5 is how many times more acidic than a sample with a pH of 7?
- 4011A pH meter is calibrated using
- 4012Turbidity is measured with a
- 4013Which of the following will give a false high turbidity reading?
- 4014Which standard is used to calibrate a turbidimeter?
- 4015Specific conductance of water is a measure of
- 4016Alkalinity is measured by titrating the sample with
- 4017Total hardness is expressed in the laboratory as
- 4018Which method uses a color change to show the presence of coliform bacteria in a 100 mL sample with only a yes or no answer?
- 4019The heterotrophic plate count (HPC) is used to
- 4020Which action reduces the risk of cross-contamination when dealing with reagents in a lab?
- 4021Safety Data Sheets (SDS) for each laboratory chemical give information on
- 4022When diluting concentrated acid in the lab, the correct procedure is to
- 4023If 10 mL of a stock solution is diluted to a final volume of 100 mL, the dilution factor is
- 4024You need 500 mL of a 2 mg/L solution from a 100 mg/L stock. How many mL of stock are required?
- 4025A sample for a metals analysis such as lead should be preserved by
- 4026When collecting a sample from a well, the operator should first
- 4028The Standard Methods approved procedure for analyzing a regulated compliance parameter must be followed because