CWEA Lab Analyst Grade 1 Exam
Review with Exam Questions and
Correct Solutions| A+
GRADED|UPDATED 2025/2026
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PASS!!<NEWEST VERSION>
analytical balance - ANSWER ✓ a device for determining mass that gives highly
accurate measurements
top loading balance - ANSWER ✓ used to determine mass; not as precise as an
analytical balance
triple beam balance - ANSWER ✓ instrument used to measure mass, less sensitive
than top loading
Coliform - ANSWER ✓ Gram-negative rod-shaped bacteria normally present in
the intestine; includes E. coli and other species.
temp and pH - ANSWER ✓ temp rises, pH drops. Must measure pH within 15
min of collecting sample
Always add ___ to ___ - ANSWER ✓ acid to water
spectrometer - ANSWER ✓ a device that spreads light into its different colors
rounding off - ANSWER ✓ .5=keep # even <.4 stays the same >.6 round up
Mass Based Limits - ANSWER ✓ Discharge limits based on allowable dry weigh
of pollutant, usually expressed in pounds per day
,Mass Emission Rate - ANSWER ✓ The rate of discharge of the dry weight of the
pollutant in wastewater or air, expressed in lb/day or kg/day
Material Safety Data Sheets (MSDS) - ANSWER ✓ Sheets providing info about
manufactured chemicals, as required by the Hazard Communication Rule
Molarity - ANSWER ✓ Moles per liter, a measure of concentration
Mole - ANSWER ✓ An avogadro's number of something
Molecular weight - ANSWER ✓ the sum of the atomic weights of all atoms
making up a molecule
National Pollutant Discharge Elimination System - ANSWER ✓ Prohibitions,
applicable to all nondomestic dischargers, regarding the introduction of pollutants
into POTWs as set forth in 40 CFR 403.5
Neutralization - ANSWER ✓ Addition of an acid or alkali (base) to a liquid to
cause the pH of the liquid to move toward a neutral pH of 7.0
Oxidation-Reduction - ANSWER ✓ Reactions that involve the transfer of
elections, with oxidation being the loss of electrons and reduction being the
gaining of elections.
Oxidation- Reduction Potential (ORP) - ANSWER ✓ A qualitative measure of the
state of oxidation in metal waste treatment systems; used to control the chemical
addition to optimize the oxidation of compounds (ie cyanide) or reduction of
metals (ie hexavelent chromium)
Parshall Flume - ANSWER ✓ An open channel flow measuring device with a
measuring device with a constricted throat that produces a head or water depth that
is related to discharge
Pass- through - ANSWER ✓ the passage of untreated pollutants through a POTW
which could violate applicable water quality standards of NPDES effluent
limitations
, pH - ANSWER ✓ the negative logarithm of the hydrogen ion concetration; the
measure of the relative acidity of alkalinity of a solution on a scale from 0 (acidic)
to 14 (alkali)
Chloride - ANSWER ✓ - Major anion found in many natural waters
- Can impart salty taste in H2O
What increases concentration of chloride in wastewater - ANSWER ✓ Chloride in
human diet and softeners flushed into sanitary sewer system
2 most prevalent methods of measuring chloride - ANSWER ✓ argentometric and
mercuric nitrate
Argentometric - ANSWER ✓ Titration of sample with standard solution of silver
nitrate (AgNO3)
- Indicator: Chromate ions (CrO4)
- End point: reddish silver chromate
Mercuric Nitrate - ANSWER ✓ Titration with standard mercuric nitrate solution
-pH must be adjusted between 2.3 and 2.8
- Indicator: Diphenyl carbazone
- End point: Change from blue to purple in presence of mercury
Interference of Mercuric Nitrate Method - ANSWER ✓ Sulfide, bromide,
orthophosphate (over 30 ppm), and iodide
Why does color change in water - ANSWER ✓ Presence of decaying vegetable
matter, metal ions (ie. iron) or industrial and domestic pollution
How is color measured - ANSWER ✓ Measured using visual comparison method
Visual comparison method - ANSWER ✓ Sample compared to standards using
matched nessler tubes
- Standards prepared with solution containing cholorplatinate and cobaltous
chloride
Standard units for color - ANSWER ✓ One unit= color resulting from 1 mg of
platinum/L
Review with Exam Questions and
Correct Solutions| A+
GRADED|UPDATED 2025/2026
SYLLABUS|100% GUARANTEED
PASS!!<NEWEST VERSION>
analytical balance - ANSWER ✓ a device for determining mass that gives highly
accurate measurements
top loading balance - ANSWER ✓ used to determine mass; not as precise as an
analytical balance
triple beam balance - ANSWER ✓ instrument used to measure mass, less sensitive
than top loading
Coliform - ANSWER ✓ Gram-negative rod-shaped bacteria normally present in
the intestine; includes E. coli and other species.
temp and pH - ANSWER ✓ temp rises, pH drops. Must measure pH within 15
min of collecting sample
Always add ___ to ___ - ANSWER ✓ acid to water
spectrometer - ANSWER ✓ a device that spreads light into its different colors
rounding off - ANSWER ✓ .5=keep # even <.4 stays the same >.6 round up
Mass Based Limits - ANSWER ✓ Discharge limits based on allowable dry weigh
of pollutant, usually expressed in pounds per day
,Mass Emission Rate - ANSWER ✓ The rate of discharge of the dry weight of the
pollutant in wastewater or air, expressed in lb/day or kg/day
Material Safety Data Sheets (MSDS) - ANSWER ✓ Sheets providing info about
manufactured chemicals, as required by the Hazard Communication Rule
Molarity - ANSWER ✓ Moles per liter, a measure of concentration
Mole - ANSWER ✓ An avogadro's number of something
Molecular weight - ANSWER ✓ the sum of the atomic weights of all atoms
making up a molecule
National Pollutant Discharge Elimination System - ANSWER ✓ Prohibitions,
applicable to all nondomestic dischargers, regarding the introduction of pollutants
into POTWs as set forth in 40 CFR 403.5
Neutralization - ANSWER ✓ Addition of an acid or alkali (base) to a liquid to
cause the pH of the liquid to move toward a neutral pH of 7.0
Oxidation-Reduction - ANSWER ✓ Reactions that involve the transfer of
elections, with oxidation being the loss of electrons and reduction being the
gaining of elections.
Oxidation- Reduction Potential (ORP) - ANSWER ✓ A qualitative measure of the
state of oxidation in metal waste treatment systems; used to control the chemical
addition to optimize the oxidation of compounds (ie cyanide) or reduction of
metals (ie hexavelent chromium)
Parshall Flume - ANSWER ✓ An open channel flow measuring device with a
measuring device with a constricted throat that produces a head or water depth that
is related to discharge
Pass- through - ANSWER ✓ the passage of untreated pollutants through a POTW
which could violate applicable water quality standards of NPDES effluent
limitations
, pH - ANSWER ✓ the negative logarithm of the hydrogen ion concetration; the
measure of the relative acidity of alkalinity of a solution on a scale from 0 (acidic)
to 14 (alkali)
Chloride - ANSWER ✓ - Major anion found in many natural waters
- Can impart salty taste in H2O
What increases concentration of chloride in wastewater - ANSWER ✓ Chloride in
human diet and softeners flushed into sanitary sewer system
2 most prevalent methods of measuring chloride - ANSWER ✓ argentometric and
mercuric nitrate
Argentometric - ANSWER ✓ Titration of sample with standard solution of silver
nitrate (AgNO3)
- Indicator: Chromate ions (CrO4)
- End point: reddish silver chromate
Mercuric Nitrate - ANSWER ✓ Titration with standard mercuric nitrate solution
-pH must be adjusted between 2.3 and 2.8
- Indicator: Diphenyl carbazone
- End point: Change from blue to purple in presence of mercury
Interference of Mercuric Nitrate Method - ANSWER ✓ Sulfide, bromide,
orthophosphate (over 30 ppm), and iodide
Why does color change in water - ANSWER ✓ Presence of decaying vegetable
matter, metal ions (ie. iron) or industrial and domestic pollution
How is color measured - ANSWER ✓ Measured using visual comparison method
Visual comparison method - ANSWER ✓ Sample compared to standards using
matched nessler tubes
- Standards prepared with solution containing cholorplatinate and cobaltous
chloride
Standard units for color - ANSWER ✓ One unit= color resulting from 1 mg of
platinum/L
