举一反三
- Water __________ oxygen (氧) and hydrogen (氢).
- Manufacturers of hydrogen generators have developed methods to use lower amounts of electricity to split water into hydrogen. Different electrolytes or catalysts are used in _______ the bonds between hydrogen and oxygen atoms that make up water.
- Water is a simple compound of two atoms of hydrogen and one atom of oxygen
- Ice is to water as () A: oxygen is to hydrogen B: snow is to helium C: water is to steam D: road is to path E: ice cream is to popsicle
- Scientists figured out that human bodies are basically made of（） A: hydrogen, carbon, nitrogen, and oxygen atoms B: water vapor, ammonia, carbon dioxide, methane and hydrogen C: biomolecules and water D: evolutionary molecules
内容
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中国大学MOOC: Water i________ a liquid made up of molecules of hydrogen and oxygen in the ratio of 2 to 1.
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According to the state of water in the soil, the liquid phase can be divided into ____, bound water, and free water.
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Most bottled water is the same as tap water. Both tap and bottled water come from rivers and _______ .
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Pure hydrogen does not occur naturally on Earth in large quantities, and it is locked up in enormous quantities in water, hydrocarbons, and other ______. One of the challenges of using hydrogen as a fuel comes from being able to efficiently extract hydrogen from these compounds (化合物).
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Which of the following is the physical properties of hydrogen? A: low density B: The boiling point of hydrogen is about -253 ℃. C: It has three isotopes. D: It reacts with oxygen to form water. E: It can react with [img=47x22]1803a8273e77b4a.png[/img] to form [img=34x19]1803a827468c498.png[/img]. F: It reacts with nitrogen to form ammonia. G: It can react with CO to form methane. H: It can react with [img=33x22]1803a8274f0cd41.png[/img] to form CO.