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　Hydrogen and Industries

Hydrogen, the lightest and simplest of the elements, has several properties that make it valuable for many industries. It releases more heat per unit of weight than any other fuel. In rocket engines, tons of hydrogen and oxygen are burned, and hydrogen is used with oxygen for welding torches that produce temperatures as high as 4, 000 degrees F and can be used in cutting steel. Fuel cells to generate electricity operate on hydrogen and oxygen.

Hydrogen also serves to prevent metals from tarnishing during heat treatments by removing the oxygen from them. Although it would be difficult to remove the oxygen by itself, hydrogen readily combines with oxygen to form water, which can be heated to steam and easily removed. Hydrogen is also useful in the food industry for a process know as hydrogenation. Products such as margarine and cooking oils are changed from liquids to semisolids by adding hydrogento their molecules. Soap manufacturers also use hydrogen for this purpose.

Hydrogen is also one of the coolest refrigerants. It does not become a liquid until it reaches temperatures of -425 degrees F. Pure hydrogen gas is used in large electric generators to cool the coils. In addition, in the chemical industry, hydrogen is used to produce ammonia, gasoline, methyl alcohol, and many other important products.

氫與工業

氫作為最輕和最簡單的無素，有幾種特性對工業非常有用。作為燃料，它每單位重量釋放熱量最多，在火箭的'引擎中，成噸的氫和氧被燃燒掉。氫和氧合在一起用於焊接，能夠產生高達華氏四千度的高溫而可以切割鋼鐵。發電的燃料房就是使用氫和氧。

氫也可以用來在金屬熱處理中通過從中除去氧的方法來防鏽。雖然單獨除去氧本身是困難的，氫和氧很容易結合成水，而水是可以加熱蒸發除去的。氫在食品工業中對於所謂的氫化過程也很有用。人造黃油和食用油的分子中加上氫，就由液態變成半固態。肥皂製造商也為此使用氫。

氫是溫度最低的冷凍劑。它要到華氏-425 度才會液化。純氫被用於大型發電機線圈的冷卻。除此之外，在化學工業中，氫被用來製造氨、汽油、甲醇以及其它許多重要產品。