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ACS ANALYTICAL CHEMISTRY EXAM
2026 QUESTIONS AND ANSWERS| ACE
YOUR GRADES.
Determinate error (systematic error) - correct answer -Sampling,
method, measurement or personal errors. Can be traced to a
source. Affect accuracy.
Indeterminate error (random error) - correct answer -Affect
precision. Can be traced to sample collection, manipulation and or
measurement.
Uncertainty - correct answer -The range of possible values for a
measurement. Can be added or subtracted via squaring each
standard deviation, performing the necessary operations (+,-) and
taking the square root.
Relative uncertainty - correct answer -Uncertainty of a quantity
divided by the value of the quantity. It is usually expressed as a
percentage of the measured quantity.
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Multiplying or dividing uncertainty - correct answer -use relative
uncertainty. Square, add, then square root. Absolute uncertainty
can be obtained by multiplying by R.
Binomial Distribution - correct answer -The probability distribution
of X with parameters n and p. Homogenous mixtures.
Confidence interval - correct answer -a range of values so defined
that there is a specified probability that the value of a parameter
lies within it. Xi = µ ± zσ : Where z is from a table.
Degrees of freedom - correct answer -The number of individual
scores that can vary without changing the sample mean.
Statistically written as 'N-1' where N represents the number of
subjects.
Normal Phase HPLC - correct answer -polar stationary phase,
non-polar mobile phase. Therefore non-polar will come out first,
polar last.
ACS ANALYTICAL CHEMISTRY EXAM
2026 QUESTIONS AND ANSWERS| ACE
YOUR GRADES.
Determinate error (systematic error) - correct answer -Sampling,
method, measurement or personal errors. Can be traced to a
source. Affect accuracy.
Indeterminate error (random error) - correct answer -Affect
precision. Can be traced to sample collection, manipulation and or
measurement.
Uncertainty - correct answer -The range of possible values for a
measurement. Can be added or subtracted via squaring each
standard deviation, performing the necessary operations (+,-) and
taking the square root.
Relative uncertainty - correct answer -Uncertainty of a quantity
divided by the value of the quantity. It is usually expressed as a
percentage of the measured quantity.
, Page | 2
Multiplying or dividing uncertainty - correct answer -use relative
uncertainty. Square, add, then square root. Absolute uncertainty
can be obtained by multiplying by R.
Binomial Distribution - correct answer -The probability distribution
of X with parameters n and p. Homogenous mixtures.
Confidence interval - correct answer -a range of values so defined
that there is a specified probability that the value of a parameter
lies within it. Xi = µ ± zσ : Where z is from a table.
Degrees of freedom - correct answer -The number of individual
scores that can vary without changing the sample mean.
Statistically written as 'N-1' where N represents the number of
subjects.
Normal Phase HPLC - correct answer -polar stationary phase,
non-polar mobile phase. Therefore non-polar will come out first,
polar last.
