75 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 hydrogen to 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.
外研版八上《Module 6 A famous story Unit 3 Language in use》word教案
外研版八上《Module 3 Unit 1 Has it arrived yet》word教案
外研版八上《Module 9 Unit 1 We need to protect animals》word导学案
外研版八上《Module 2 Unit 2 Wei Ming has been all over China by plane》word教案
外研版八上《Module 4 Education Unit 2 Project Hope has built many schools》word教案
外研版八上《Module 3 Journey to space》word全模块教案1
外研版八上《Module 7 Unit 1 That smells delicious》word教案1
外研版八上《Module 7 Unit 1 That smells delicious》word教案
外研版八上《Module 8 Around town》word复习资料
外研版八上《Module 6 A famous story Unit 3 Language in use》word教案1
外研版初二英语上Module 8复习教案
外研版八上《Module 8 Unit 2 The London Eye is on your right》word教案
外研版八上《Module 6 Unit 1 She was sitting by the river》word教案2
外研版八上《Module 12 Traditional life》word全模块教案1
外研版八上《Module 4 Education》word学案
外研版八上《Module 9 Animals in danger》word复习资料
外研版八上《Module 6 Unit 1 She was sitting by the river》word教案
外研版八上《Module 2 Unit 2 Wei Ming has been all over China by plane》word教案1
外研版八上《Module 6 Unit 1 She was sitting by the river》word教案1
外研版八上《Module 2 Experiences》word词组汇总
外研版八上《Module 2 Experiences》word全模块教案
外研版八上《Module 4 Education Unit 1 How long have you studied English》word教案
外研版八上《Module 12 Traditional life》word复习资料
外研版八上《Module 7 Feelings and impressions》word全模块教案
外研版八上《Module 3 Unit 2 We haven’t found life on other planets yet》word教案
外研版八上《Module 7 Unit 2 I feel nervous when I speak Chinese》word教案
外研版八上《Module 5 Western music》word全模块教案
外研版八上《Module 7 Feelings and impressions》word教案
外研版八上《Module 3 Journey to space》word全模块教案
外研版八上《Module 12 Unit 3 Language in use》word教案
不限 |
英语教案 |
英语课件 |
英语试题 |
不限 |
不限 |
上册 |
下册 |
不限 |