1 Exampromax - Stuvia US 2025/2026
CWEA - LAB ANALYST III (CWEA
CERTIFICATION TEST) 2025 QUESTIONS
WITH 100% SOLVED SOLUTIONS!! A+
What does COLOR measure?
Ans: Amount of color units (CU) in a sample. Color caused by natural metallic
ions (Fe & Mg) & industrial wastes.
What is the test summary for COLOR?
Ans: Sample -> Tubes -> Compare to color standards over light source
© 2025 Assignment Expert
Which of the following techniques is used to isolate anionic surfactants (as
MBAS) from the sample matrix?
Exampromax - Stuvia US
Ans: Extraction
In the cyanide determination, which one of the following is not an
interference?
Ans: Halogenated aromatics
Which of the following is not a major interference in phenol determination?
Ans: Hydroxy derivatives of benzene
A freshly prepared sodium hydroxide (NaOH) solution is standardized
against primary standard potassium acid phthalate (KHC8H4O4). 0.8000
grams of potassium acid phthalate was dissolved into 50 mL CO2-free
water. 2-3 drops of phenolphthalein were added. The sample was titrated to
a faint pink endpoint with 22 mLs sodium hydroxide. What is the normality
of the sodium hydroxide?
Ans: 0.178 N
What does an ICP source consist of?
Ans: A flowing stream of argon gas ionized by an applied radio frequency
, 2 Exampromax - Stuvia US 2025/2026
In gas chromatography, electron capture detectors (ECD) are used to detect
which of the following compounds?
Ans: Chlorinated hydrocarbon pesticides
Why is methlyene chloride replaced by hexane in sample preparation for
analyses detected by GC electron capture detection (ECD)?
Ans: Chlorine compounds are detected by ECD
Which of the following methods is used to determine pesticides?
Ans: EPA Method 608
What analysis uses the purge and trap technique?
© 2025 Assignment Expert
Ans: Volatile organic compound analysis
Exampromax - Stuvia US
The test for inhibitory residues on glassware and plastic ware determines
the toxic or stimulatory effects of dishwashing detergents used for bacterial
analysis. Which bacterial genera is used for this test?
Ans: Enterobacter
The Water Suitability Test (Test for Bacteriological Quality of Reagent
Water) determines the toxic or stimulatory effects of the distilled or
deionized water system. Which bacteria genera is used for this test?
Ans: Enterobacter
Short-term toxicity tests are inappropriate for:
Ans: determining chronic toxicity.
Basic requirements for toxicity tests do not include:
Ans: documented re-use of control test organisms.
A test in which solutions and test organisms are placed in test chambers
and kept there for the duration of the test is called a:
Ans: static test.
CWEA - LAB ANALYST III (CWEA
CERTIFICATION TEST) 2025 QUESTIONS
WITH 100% SOLVED SOLUTIONS!! A+
What does COLOR measure?
Ans: Amount of color units (CU) in a sample. Color caused by natural metallic
ions (Fe & Mg) & industrial wastes.
What is the test summary for COLOR?
Ans: Sample -> Tubes -> Compare to color standards over light source
© 2025 Assignment Expert
Which of the following techniques is used to isolate anionic surfactants (as
MBAS) from the sample matrix?
Exampromax - Stuvia US
Ans: Extraction
In the cyanide determination, which one of the following is not an
interference?
Ans: Halogenated aromatics
Which of the following is not a major interference in phenol determination?
Ans: Hydroxy derivatives of benzene
A freshly prepared sodium hydroxide (NaOH) solution is standardized
against primary standard potassium acid phthalate (KHC8H4O4). 0.8000
grams of potassium acid phthalate was dissolved into 50 mL CO2-free
water. 2-3 drops of phenolphthalein were added. The sample was titrated to
a faint pink endpoint with 22 mLs sodium hydroxide. What is the normality
of the sodium hydroxide?
Ans: 0.178 N
What does an ICP source consist of?
Ans: A flowing stream of argon gas ionized by an applied radio frequency
, 2 Exampromax - Stuvia US 2025/2026
In gas chromatography, electron capture detectors (ECD) are used to detect
which of the following compounds?
Ans: Chlorinated hydrocarbon pesticides
Why is methlyene chloride replaced by hexane in sample preparation for
analyses detected by GC electron capture detection (ECD)?
Ans: Chlorine compounds are detected by ECD
Which of the following methods is used to determine pesticides?
Ans: EPA Method 608
What analysis uses the purge and trap technique?
© 2025 Assignment Expert
Ans: Volatile organic compound analysis
Exampromax - Stuvia US
The test for inhibitory residues on glassware and plastic ware determines
the toxic or stimulatory effects of dishwashing detergents used for bacterial
analysis. Which bacterial genera is used for this test?
Ans: Enterobacter
The Water Suitability Test (Test for Bacteriological Quality of Reagent
Water) determines the toxic or stimulatory effects of the distilled or
deionized water system. Which bacteria genera is used for this test?
Ans: Enterobacter
Short-term toxicity tests are inappropriate for:
Ans: determining chronic toxicity.
Basic requirements for toxicity tests do not include:
Ans: documented re-use of control test organisms.
A test in which solutions and test organisms are placed in test chambers
and kept there for the duration of the test is called a:
Ans: static test.
