List (a) three commercial means of producing \(\mathrm{H}_{2},\) (b) three industrial uses of \(\mathrm{H}_{2}\).

There are several commercial methods for producing hydrogen gas. Here are three common methods: 1. Electrolysis: This method involves passing an electric current through water, causing it to split into hydrogen and oxygen. This is typically done using an electrolytic cell with a cathode and an anode, separating the hydrogen and oxygen gas that is produced. 2. Steam-methane reforming: This is the most common method for producing hydrogen gas commercially. In this process, methane or natural gas reacts with steam at high temperatures (700-1100°C) in the presence of a catalyst, producing a mixture of hydrogen, carbon monoxide, and carbon dioxide. The hydrogen is then separated from the other gases and purified. 3. Coal gasification: This process involves reacting coal with oxygen and steam at high temperatures, producing a mixture of hydrogen, carbon monoxide, and carbon dioxide. The hydrogen is then separated from other gases and purified.

Hydrogen gas has numerous applications in various industries. Here are three industrial uses of hydrogen: 1. Chemical industry: Hydrogen is used as a raw material in the production of various chemicals, such as ammonia, methanol, and hydrochloric acid. Ammonia production, in particular, is a significant consumer of hydrogen, where it reacts with nitrogen in the Haber-Bosch process to produce ammonia, which is widely used for making fertilizers, explosives, and other chemical products. 2. Petroleum refining: In oil refineries, hydrogen is used to remove impurities like sulfur from crude oil, a process known as hydrodesulfurization. It is also used in hydrocracking, the process of breaking down long hydrocarbon chains into shorter and more desirable ones like gasoline and diesel fuels. 3. Fuel Cells: Hydrogen fuel cells are an emerging technology that generates electricity through an electrochemical process that combines hydrogen and oxygen. These fuel cells have the potential to provide power for vehicles, homes, and industries, with water being the only byproduct, making them a clean and sustainable power source.