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 fro
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）.
A.organic matter
B.plants
C.inorganic matter
D.fossil fuels
正确答案：organic matter
- 上一篇：Fuel cells are versatile as they can scale up easily and meet a variety of power needs – large or small.You can（）individual fuel cells to increase the amount of power they can provide.The taller the stack， the more power you have.
- 下一篇：（）is an energy form found in nature that has not been subjected to any human engineered conversion process.It is energy contained in raw fuels， and other forms of energy received as input to a system.