Chapter A1, Problem A1.23QAP

Interpretation Introduction

(a)

Interpretation:

The calibration of calcium ion selective electrode is used for the determination of pC_a and the table for this data is shown below-

${\text{pC}}_a=-\log \left[C{a}^{2+}\right]$	$E_{y}mV$
5.00	-53.8
4.00	-27.7
3.00	+2.7
2.00	+31.9
1.00	+65.1

The relation between potential and the and the pC_a is linear. Using the data, a least square straight line is to be plotted using the spreadsheet.

Concept introduction:

The least square method is a method in which the best result is obtained for the set data point by minimizing the sum of offset or residuals from the plot of curve statistically.

Interpretation Introduction

(b)

Interpretation:

The least square expression is to be determined for the best straight line through the point.

Concept introduction:

The least square method is a method in which the best result is obtained for the set data point by minimizing the sum of offset or residuals from the plot of curve statistically.

Interpretation Introduction

(c)

Interpretation:

The standard deviation is to be determined for the slope and the intercept of the least-square line.

Concept introduction:

The slope of line is also called as gradient of line which is used to define the direction and steepness of the line.

The intercept line is the y −axis of line at which point it crosses X −axis.

Interpretation Introduction

(d)

Interpretation:

The value pC_a of serum solution is to be determined in which the electrode potential value is 10.7mV. The absolute and relative standard deviation for pC_a is to be determined when obtained result is from the single voltage measurement.

Concept introduction:

The standard deviation method is used for the quantification of the amount of variation or for the dispersion for the set of the data values.

Interpretation Introduction

(e)

Interpretation:

The absolute and relative standard deviation for pC_a is to be determined when the result obtained from the part (d) in millimeters is the mean value of two replicate measurements and this calculation is to be repeated for the eight measurements.

Concept introduction:

The standard deviation method is used for the quantification of the amount of variation or for the dispersion for the set of the data values.