Procedure:

● Prepare four solutions of potassium ferricyanide solutions having concentrations of 0.01 mM, 0.1 mM, 1 mM, and 10 mM.
● Prepare the solutions in a 100 ml volumetric flask.
● Take 10µl of each solution using a micropipette and place it on a screen-printed electrode.
● Analyze the graph obtained from all four solutions.
● The graph represents the impedance responses of different concentrations of K₃Fe(CN)₆ in the Nyquist format.

Calculations:

● Prepare 0.01mM of potassium ferricyanide solution
Required concentration = 0.01 mM = 1 × 10^⁻⁵ M
Molecular weight of K₃[Fe(CN)₆] = 329.24 g mol^⁻¹
Volume of solution = 100 mL = 0.1 L
Mass=M×V×Molecular weight
=(1×10⁻⁵)×0.1×329.24
=0.000329 gm

● Prepare 0.1mM of potassium ferricyanide solution
Required concentration = 0.1 mM = 1 × 10^-4 M
Molecular weight of K₃[Fe(CN)₆] = 329.24 g mol^⁻¹
Volume of solution = 100 mL = 0.1 L
Mass=M×V×Molecular weight
=(1×10⁻⁴)×0.1×329.24
=0.00329 gm

● Prepare 0.1mM of potassium ferricyanide solution
Required concentration = 1 mM = 1 × 10^-3 M
Molecular weight of K₃[Fe(CN)₆] = 329.24 g mol ^⁻¹
Volume of solution = 100 mL = 0.1 L
Mass=M×V×Molecular weight
=(1×10 ⁻³)×0.1×329.24
=0.0329 gm
● Prepare 10mM of potassium ferricyanide solution
Required concentration = 1 mM = 1 × 10^-2 M
Molecular weight of K₃[Fe(CN)₆] = 329.24 g mol^⁻¹
Volume of solution = 100 mL = 0.1 L
Mass=M×V×Molecular weight
=(1×10⁻²)×0.1×329.24
=0.329 gm