Question

The usage of dihydrogen is
(a). It acts as a fuel cell.
(b). Energy is distributed in the form of dihydrogen
(c). It is economical fuel.
(d). All of the above

Answer 1

Dihydrogen has many applications from electrochemical cells which releases more energy in comparison to diesel and petrol. Therefore, scientists have coined the term ‘Hydrogen Economy’ with a vision of using low-carbon energy sources. This gas has high efficiency and is comparatively cheap compared to other energy sources.

Complete step by step answer:
Hydrogen has a very high calorific value and heat output. Its high heating value gives better ignition temperature and sufficient flame sustaining time. Due to the large abundance of dihydrogen, it can be used as a fuel which is highly economical for its commercial usage.
A fuel cell is like a battery that generates electricity from an electrochemical reaction. A hydrogen fuel cell is an electrochemical cell that uses a spontaneous redox reaction to produce current that can do work. The net reaction is exothermic. Combining the 2 half-cell potentials for the electrochemical reaction gives a positive cell potential.
$\text{At Anode: }{{\text{H}}_{2}}\to 2{{H}^{+}}+2{{e}^{-}}$
$\text{At Cathode: }\frac{1}{2}{{\text{O}}_{2}}\text{+}2{{H}^{+}}+2{{e}^{-}}\to {{\text{H}}_{2}}\text{O}$
The energy released in the form of $\Delta {{\text{G}}_{f}}\text{= -229KJ/mol}$.
Additional Information
The hydrogen flows to a platinum catalyst connected to the anode. Molecular hydrogen is dissociated to atomic hydrogen on the metal surface and the atomic hydrogen is oxidized. The protons travel through a solid electrolyte, the polymer electrolyte membrane or PEM, and the electrons travel through the external circuit. Molecular oxygen is reduced at the cathode and combined with protons to form water.

Therefore, the correct option is (d), All of the above.

Note: It should be noted that most hydrogen is made from natural gas and petroleum. It can also be produced from coal in the water gas and water gas shift reactions. All of these use the energy stored in fossil fuels and generate $C{{O}_{2}}$ .