Currently, most hydrogen is made this way from natural gas. An electrical current can also be used to separate water into its components of oxygen and hydrogen. This process is known as electrolysis. Some algae and bacteria, using sunlight as their energy source, even give off hydrogen under certain conditions.
Originally, metal roofs were made of corrugated galvanized steel: a wrought ironâsteel sheet was coated with zinc and then roll-formed into corrugated sheets. Another approach is to blend zinc, aluminum, and silicon-coated steel.
Making steel from iron. Most steel is made from pig iron (remember: that's an iron alloy containing up to 4 percent carbon) by one of several different processes designed to remove some of the carbon and (optionally) substitute one or more other elements.ure iron is too soft and reactive to be of much real use, so most of the iron we tend to use for everyday purposes is actually in the form of iron alloys: iron mixed with other elements (especially carbon) to make stronger, more resilient forms of the metal including steel.