The cell constant G* is calculated by the expression:a)l/Ab)A.lc)l.Ad)A/lCorrect answer is option 'A'. Can you explain this answer?

Question

Answer

The quantity l/A is called cell constant denoted by the symbol, G*.It depends on the distance between the electrodes and their area of cross-section and has the dimension of length–1 and can be calculated if we know l and A. Measurement of l and A is not only inconvenient but also unreliable. The cell constant is usually determined by measuring the resistance of the cell containing a solution whose conductivity is already known. For this purpose, we generally use KCl solutions whose conductivity is known accurately at various concentrations and at different temperatures. The cell constant, G*, is then given by the equation:
G* =l/A= Rκ

Answer

It is a straight forward formula for cell constant of a cell
where l=length of the cell
A=area of cell
wkt,
R=(resistivity)×l/A
=(resistivity)×cell constant

Answer

Calculation of Cell Constant G*

The cell constant G* is a parameter used to determine the conductivity of a solution in a conductivity cell. It is calculated using the expression G* = l / A, where l represents the length of the cell and A represents the cross-sectional area of the cell.

Explanation:

1. Length of the Cell (l):
The length of the cell (l) refers to the distance between the two electrodes inside the conductivity cell. It is typically measured in centimeters (cm). The length of the cell affects the resistance of the solution being measured. A longer cell length results in a higher resistance, while a shorter cell length results in a lower resistance.

2. Cross-sectional Area of the Cell (A):
The cross-sectional area of the cell (A) refers to the area of the electrode surface that is exposed to the solution being measured. It is typically measured in square centimeters (cm^2). The cross-sectional area of the cell affects the current passing through the solution. A larger cross-sectional area allows for a greater current flow, while a smaller cross-sectional area restricts the current flow.

3. Cell Constant (G*):
The cell constant (G*) is a measure of the cell's ability to conduct electricity. It is calculated by dividing the length of the cell (l) by the cross-sectional area of the cell (A). The unit of cell constant is typically expressed as cm^-1.

4. Significance of Cell Constant:
The cell constant is an important parameter used to convert the measured conductance of a solution into its true conductivity. Conductance (G) is the reciprocal of resistance (R), and conductivity (κ) is the reciprocal of resistivity (ρ). By knowing the cell constant, we can accurately determine the conductivity of a solution using the measured conductance.

Conclusion:
The expression G* = l / A is used to calculate the cell constant, which is a parameter used to determine the conductivity of a solution in a conductivity cell. The length of the cell (l) and the cross-sectional area of the cell (A) are the two factors used in this calculation. The cell constant is essential for accurately converting measured conductance into conductivity.

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