(a)
Interpretation:
The calibration curve should be constructed in a spread sheet.
Concept introduction:
A calibration curve or standard curve is a method used in analytical chemistry to determine the concentration of unknown sample by comparing to a set of samples with known concentrations.
(b)
Interpretation:
The least square slope and the intercept for the plot in (a) should be determined.
Concept introduction:
The slope of the line,
The intercept,
(c)
Interpretation:
The standard deviation of the slope and the standard deviation about regression for the curve should be determined.
Concept introduction:
Standard deviation about regression,
N − number of points used.
The standard deviation of the slope,
The standard deviation of the intercept,
(d)
Interpretation:
The concentration of unknown NADH sample should be calculated using the spreadsheet.
Concept introduction:
A calibration curve or standard curve is a method used in analytical chemistry to determine the concentration of unknown sample by comparing to a set of samples with known concentrations.
(e)
Interpretation:
The relative standard deviation for the result in part (d) should be calculated.
Concept introduction:
Standard deviation of the results obtained from the calibration curve =
M − number of replicates
N- number of calibration points.
RSD − relative standard deviation
x - mean of x values
s − standard deviation
(f)
Interpretation:
The relative standard deviation for the result in part (d) should be calculated if a result of 7.95 was the mean of three measurements.
Concept introduction:
Standard deviation of the results obtained from the calibration curve =
M − number of replicates
N- number of calibration points.
RSD − relative standard deviation
x - mean of x values
s − standard deviation
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Chapter 15 Solutions
Principles of Instrumental Analysis
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