Hydrogen gas generation and applications (Essay Sample)

Name: University: Course: Tutor: Date: Hydrogen gas generation and applications Hydrogen is the lightest known gaseous element when studied under room temperature and standard pressures in the globe but a strong energy carrier. The process of decomposing water into its constituent components; oxygen (O2) and the hydrogen gas (H2) which is achieved by passing an electric current via the water is called electrolysis. The process set up involves the connection of two electrodes, the anode and the cathode to an electric power supply. The negatively charged electrode on to which the hydrogen electron adheres to is called the cathode and the positively charged electrode on to which oxygen molecules adheres to is the anode. These metal plates are made of inert substance like platinum or the stainless steel. During this process, the ratio of hydrogen moles generated is twice as much as the amount of oxygen moles so long as the faradaic efficiency is ideal (Hyfleet, n.d). In most cases however, the reaction generates less moles of the products because of reactions that may occur on the cells surface. Pure water usually requires a lot of activation energy to overcome the covalent bond in the water molecules hence electrolysis in pure water can be considerably slow if the much electrical energy is not provided. If the process is found to be slow, an electrolyte can be added to the reaction to activate the reaction of the inert electrodes (Cohen, 2004, p.11). The cathode reaction is a reduction process because the electrons on the cathode are donated to the hydrogen cations forming hydrogen gas. The reaction is as follows; Cathode: 2H+ (aq) + 2e-→ H2 (g). On the other hand, oxidation reaction takes place on the positively charged anode to result in the generation of the oxygen gas. The equation is as shown, Anode: 2H2O (l) → O2 (g) + 4H+ (aq) +4e- . There are other forms of half reactions that take place, and are balanced by the base or acid although not all cases can be balanced by acid or base reaction. Cathode 2H2O(l) + 2e- → H2(g) + 2 OH-(aq) (reduction reaction), while the anode reaction is; 4OH-(aq)→ O2(g) + 2H2O(l)+4e- (oxidation reaction). When the two reactions are combined, they result into the following reaction equation; Overall reaction: 2H2O(l)→ 2H2(g) + O2(g) (Kamarev, 2003). Hydrogen can be generated both in small scale and in industrial generation. The Hofmann voltmeter is one of the small scale electrolyte with platinum plates used as the anode and the cathode. The industrial electrolysis cells are also designed much like the Hofmann voltmeter, but it has very complex honeycombs or the platinum plate...