Lab Analyst Complete Set questions with correct
answers
An amperometric titration is often used when measuring Correct Answer -
Residual chlorine
The most important reason for chlorinating effluent is Correct Answer -
Disinfection
Chlorination serves primarily to destroy or deactivate disease-producing
microorganisms
When wastewater samples are chlorinated and the pH is lowered Correct Answer -
HCLO is formed
Hypochlorous acid
Which of the following constituents is the best disinfecting agent? Correct Answer
- HClO
What is most likely to interfere with the DPD test? Correct Answer - Oxidized
manganese
How is N, N-diethyl-p-phenylenediamine more commonly represented? Correct
Answer - DPD
The chlorine residual may be determined using the reagent Correct Answer - DPD
The quantity of chlorine that is converted to inert or less active forms of chlorine
by substances in wastewater Correct Answer - Total combined chlorine
,Before you perform an amperometric titration for total residual chlornie, what two
solutions should be added to the sample? Correct Answer - Kl and acetate buffer
(Potassium iodide)
When performing an amperometric titration for chlorine, how many milliliters of
sample should be analyzed? Correct Answer - 200 mL
When using a spectrophotometer to measure chlorine, what wave length of light
should be used? Correct Answer - 515 nm
An effluent with a high level of ammonia nitrogen has chlorine residual that is
mostly Correct Answer - Combined chlorine
The mercuric nitrate titration technique for measuring chloride is falling into disuse
in the laboratory because the: Correct Answer - technique is lengthy and requires
highly skilled instrument technicians to accurately analyze the samples.
Standard phenylarsine oxide solution (PAO): Correct Answer - should be handled
with caution because it is a severe poison.
Sample Protocol for chloride includes Correct Answer - glass or plastic container
with no preservative
Flow proportional sample. If total sample volume is 1 liter Correct Answer - 100ml
The incubator for the BOD determination should be monitored and recorded daily.
The incubator temperature should be: Correct Answer - 20 degrees +/-1 degree C
,Laboratory data mistakes may be corrected by: Correct Answer - lining out the
mistake with pen and writing the correct answer to the side of the first with analyst
initials and date
The sample receiving log must record time and date sampled: Correct Answer -
sample collector, nature of sample, analyses to be performed, preservatives,
condition of sample and sample recipient.
Hood flow should be monitored and documented at: Correct Answer - 100 linear
feet per minute
During an acid base titration, the titrant is added to the sample with a: Correct
Answer - Buret
Separatory funnels are designed to facilitate liquid-liquid extractions. Liquid-liquid
extraction can be used to separate Correct Answer - organic analytes from the
water by partitioning them into an organic solvent
At a given temperature the intensity of the acidic or basic character of a solution is
indicated by Correct Answer - pH or Hydrogen ion activity
A solution with a pH of 5 has a concentration of hydrogen ions that is how many
times higher than a solution with a pH if 7? Correct Answer - 100 times higher
A pH measurement requires the following: Correct Answer - a voltmeter, glass pH
electrode, reference electrode, and temperature compensating device
, Conductance measurements are temperature compensated to: Correct Answer -
25.0 C
The conductivity meter is calibrated with: Correct Answer - .0100 N potassium
chloride standard
Alkalinity is reported as: Correct Answer - alkalinity, mg CaCO3/L
The hardness determination by EDTA titration measures: Correct Answer -
Calcium and Magnesium
The indicator for the hardness determination is: Correct Answer - eriochrome
Black T
EPA acceptable primary standards for the turbidity determination include: Correct
Answer - formazine only
COD Correct Answer - ((Blank-Sample) x M x 8000))/ml Sample
The Biochemical Oxygen Demand determination is an empirical test in which
standardized laboratory procedures are used to: Correct Answer - determine the
relative oxygen requirements of wastewaters, effluents and polluted waters.
Sample pretreatment for the BOD determination includes Correct Answer -
assuring that the samples are neutralized to a pH range between 6.5 and 7.5 and
that any residual chlorine has been dechlorinated
The process designed to kill most microorganisms in wastewater, including
essentially all pathogenic bacteria is called: Correct Answer - disinfection
answers
An amperometric titration is often used when measuring Correct Answer -
Residual chlorine
The most important reason for chlorinating effluent is Correct Answer -
Disinfection
Chlorination serves primarily to destroy or deactivate disease-producing
microorganisms
When wastewater samples are chlorinated and the pH is lowered Correct Answer -
HCLO is formed
Hypochlorous acid
Which of the following constituents is the best disinfecting agent? Correct Answer
- HClO
What is most likely to interfere with the DPD test? Correct Answer - Oxidized
manganese
How is N, N-diethyl-p-phenylenediamine more commonly represented? Correct
Answer - DPD
The chlorine residual may be determined using the reagent Correct Answer - DPD
The quantity of chlorine that is converted to inert or less active forms of chlorine
by substances in wastewater Correct Answer - Total combined chlorine
,Before you perform an amperometric titration for total residual chlornie, what two
solutions should be added to the sample? Correct Answer - Kl and acetate buffer
(Potassium iodide)
When performing an amperometric titration for chlorine, how many milliliters of
sample should be analyzed? Correct Answer - 200 mL
When using a spectrophotometer to measure chlorine, what wave length of light
should be used? Correct Answer - 515 nm
An effluent with a high level of ammonia nitrogen has chlorine residual that is
mostly Correct Answer - Combined chlorine
The mercuric nitrate titration technique for measuring chloride is falling into disuse
in the laboratory because the: Correct Answer - technique is lengthy and requires
highly skilled instrument technicians to accurately analyze the samples.
Standard phenylarsine oxide solution (PAO): Correct Answer - should be handled
with caution because it is a severe poison.
Sample Protocol for chloride includes Correct Answer - glass or plastic container
with no preservative
Flow proportional sample. If total sample volume is 1 liter Correct Answer - 100ml
The incubator for the BOD determination should be monitored and recorded daily.
The incubator temperature should be: Correct Answer - 20 degrees +/-1 degree C
,Laboratory data mistakes may be corrected by: Correct Answer - lining out the
mistake with pen and writing the correct answer to the side of the first with analyst
initials and date
The sample receiving log must record time and date sampled: Correct Answer -
sample collector, nature of sample, analyses to be performed, preservatives,
condition of sample and sample recipient.
Hood flow should be monitored and documented at: Correct Answer - 100 linear
feet per minute
During an acid base titration, the titrant is added to the sample with a: Correct
Answer - Buret
Separatory funnels are designed to facilitate liquid-liquid extractions. Liquid-liquid
extraction can be used to separate Correct Answer - organic analytes from the
water by partitioning them into an organic solvent
At a given temperature the intensity of the acidic or basic character of a solution is
indicated by Correct Answer - pH or Hydrogen ion activity
A solution with a pH of 5 has a concentration of hydrogen ions that is how many
times higher than a solution with a pH if 7? Correct Answer - 100 times higher
A pH measurement requires the following: Correct Answer - a voltmeter, glass pH
electrode, reference electrode, and temperature compensating device
, Conductance measurements are temperature compensated to: Correct Answer -
25.0 C
The conductivity meter is calibrated with: Correct Answer - .0100 N potassium
chloride standard
Alkalinity is reported as: Correct Answer - alkalinity, mg CaCO3/L
The hardness determination by EDTA titration measures: Correct Answer -
Calcium and Magnesium
The indicator for the hardness determination is: Correct Answer - eriochrome
Black T
EPA acceptable primary standards for the turbidity determination include: Correct
Answer - formazine only
COD Correct Answer - ((Blank-Sample) x M x 8000))/ml Sample
The Biochemical Oxygen Demand determination is an empirical test in which
standardized laboratory procedures are used to: Correct Answer - determine the
relative oxygen requirements of wastewaters, effluents and polluted waters.
Sample pretreatment for the BOD determination includes Correct Answer -
assuring that the samples are neutralized to a pH range between 6.5 and 7.5 and
that any residual chlorine has been dechlorinated
The process designed to kill most microorganisms in wastewater, including
essentially all pathogenic bacteria is called: Correct Answer - disinfection
