Electrochemistry, Rechargeable Batteries and Fuel Cells

Using the Nernst equation, calculate emf of the following cell at $298 \mathrm{K}$:

$\mathrm{Cr}\left(\mathrm{s}\right) \left| {\mathrm{Cr}}^{3+}\left(0.1 \mathrm{M}\right) \right|\left| {\mathrm{Fe}}^{2+}\left(0.01\mathrm{M}\right) \right|\mathrm{Fe}\left(\mathrm{s}\right)$

Given that,

$$\begin{gathered} {\mathrm{E}}_{{\mathrm{Cr}}^{3+}/\mathrm{Cr}}^{\circ }=-0.75 \mathrm{V} \\ {\mathrm{E}}_{{\mathrm{Fe}}^{2+}/\mathrm{Fe}}^{\circ }=-0.45 \mathrm{V} \end{gathered}$$

$\frac{2.303\mathrm{RT}}{\mathrm{F}}=0.0591\mathrm{V}$

Discuss the relation between free energy and EMF.

Discuss conjugated system by giving example.

Which of the following has the highest energy density?

Among methanol fuel cell and lithium-ion battery, which has higher energy density?

In alkali fuel cell, ${\mathrm{OH}}^{-}$ ions migrate towards the cathode and produce water on reaction with ${\mathrm{H}}^{+}$ ions.

Name the electrolyte used in alkali fuel cell.

Nickel-cadmium battery has high internal resistance allows for a quick recharge time.

Write two advantages of Nickel-cadmium battery.

The charge specific density of lithium-ion battery is less compared to lead-acid battery.

Write any three advantages of lithium-ion battery.

Write the charging and discharging reactions occuring in the lithium ion battery.

Name the anode and cathode used in lithium-ion batteries.

Select whether the following statement is True or False:

A typical lead-acid battery is an example of a primary electrochemical cell or non-rechargeable battery.

Write a short note on the classification of electrical batteries.

Why longer conjugated systems absorbing light of longer wavelength?

Molecules with _____ bonds can absorb visible light, with longer conjugated systems absorbing light of longer wavelength. (conjugated/non-conjugated)

Give the fuel used in the microbial fuel cells.

Explain the microbial fuel cells?

_____ is the ratio of the Gibbs energy change to the enthalpy change.