CWEA GRADE 1 LAB ANALYST EXAM ACTUAL EXAM 200 QUESTIONS AND CORRECT DETAILED
ANSWERS WITH RATIONALES |AGRADE
Celcius - ANSWER-(F-32)5/9
HPC media water bath - ANSWER-45`C, 3hr
Precision - ANSWER-a measure of how close a series of measurements are to one another
Accuracy - ANSWER-how close a measurement is to the true value
Electrical Fire - ANSWER-unplug & sodium bicarbonate
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
sig fig rules - ANSWER-Non-zero digits are always significant.
Any zeros between two significant digits are significant.
A final zero or trailing zeros in the decimal portion ONLY are significant.
adding sig figs - ANSWER-smallest number of decimals
Alkalinity hold time - ANSWER-14 days
COD hold time - ANSWER-28 days
BOD hold time - ANSWER-48 hours
ANSWERS WITH RATIONALES |AGRADE
Celcius - ANSWER-(F-32)5/9
HPC media water bath - ANSWER-45`C, 3hr
Precision - ANSWER-a measure of how close a series of measurements are to one another
Accuracy - ANSWER-how close a measurement is to the true value
Electrical Fire - ANSWER-unplug & sodium bicarbonate
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
sig fig rules - ANSWER-Non-zero digits are always significant.
Any zeros between two significant digits are significant.
A final zero or trailing zeros in the decimal portion ONLY are significant.
adding sig figs - ANSWER-smallest number of decimals
Alkalinity hold time - ANSWER-14 days
COD hold time - ANSWER-28 days
BOD hold time - ANSWER-48 hours
