CWEA grade 1 lab analyst prac ce test part 2 With
complete solu on Rated A+ 2025/2026 NEW!!
What is chloride?
Major anion found in many natural waters - Can impart salty taste in H2O
1 mul ple choice op on
What increases the concentra on of chloride in wastewater?
Chloride in human diet and so eners flushed into sanitary sewer system
2 most prevalent methods of measuring chloride?
argentometric and mercuric nitrate
What is the Argentometric method?
Titra on of the sample with a standard solu on of silver nitrate (AgNO3) - Indicator: Chromate
ions (CrO4) - End point: reddish silver chromate
What is the Mercuric Nitrate method?
Titra on with standard mercuric nitrate solu on -pH must be adjusted between 2.3 and 2.8 -
Indicator: Diphenyl carbazone - End point: Change from blue to purple in the presence of
mercury
Which of the following can be an Interference of the Mercuric Nitrate Method?
Sulfide, bromide, orthophosphate (over 30 ppm), and iodide
Why does the color change in water?
a. Presence of decaying vegetable ma6er
b. metal ions (ie. iron)
c. industrial and domes c pollu on
d. All of the above
, d
How is color measured
Measured using visual comparison method
1 mul ple choice op on
What is the visual comparison method
Sample compared to standards using matching nessler tubes - Standards prepared with solu on
containing chloropla nate and cobaltous chlorid
What is the standard unit for color?
One unit= color resul ng from 1 mg of pla num/L
What is 2-color repor ng?
True and Apparent
1 mul ple choice op on
Define True color
Color from suspended solids, determine using sample treated to remove turbidity
What is Apparent Color?
Color from both dissolved and suspended solids
What is Conduc vity?
H2O capability to pass electrical flow
What is the conduc vity of pure water?
0
complete solu on Rated A+ 2025/2026 NEW!!
What is chloride?
Major anion found in many natural waters - Can impart salty taste in H2O
1 mul ple choice op on
What increases the concentra on of chloride in wastewater?
Chloride in human diet and so eners flushed into sanitary sewer system
2 most prevalent methods of measuring chloride?
argentometric and mercuric nitrate
What is the Argentometric method?
Titra on of the sample with a standard solu on of silver nitrate (AgNO3) - Indicator: Chromate
ions (CrO4) - End point: reddish silver chromate
What is the Mercuric Nitrate method?
Titra on with standard mercuric nitrate solu on -pH must be adjusted between 2.3 and 2.8 -
Indicator: Diphenyl carbazone - End point: Change from blue to purple in the presence of
mercury
Which of the following can be an Interference of the Mercuric Nitrate Method?
Sulfide, bromide, orthophosphate (over 30 ppm), and iodide
Why does the color change in water?
a. Presence of decaying vegetable ma6er
b. metal ions (ie. iron)
c. industrial and domes c pollu on
d. All of the above
, d
How is color measured
Measured using visual comparison method
1 mul ple choice op on
What is the visual comparison method
Sample compared to standards using matching nessler tubes - Standards prepared with solu on
containing chloropla nate and cobaltous chlorid
What is the standard unit for color?
One unit= color resul ng from 1 mg of pla num/L
What is 2-color repor ng?
True and Apparent
1 mul ple choice op on
Define True color
Color from suspended solids, determine using sample treated to remove turbidity
What is Apparent Color?
Color from both dissolved and suspended solids
What is Conduc vity?
H2O capability to pass electrical flow
What is the conduc vity of pure water?
0
