20.3.3 Fuel Cells and The Hydrogen Economy Flashcards
Some internal combustion engines are able to use compressed natural gas (CNG) as a fuel source. The products of complete CNG combustion are carbon dioxide and water. What are the likely products produced by the combustion of hydrogen gas in such an engine?
Water only
Why is hydrogen considered a good potential fuel source?
The product of hydrogen combustion is only water
Which of the following compounds is a greenhouse gas?
Carbon dioxide
Though hydrogen gas can be used directly as a fuel in a (modified) internal combustion engine, it is not efficient. Why not?
Most of the energy of the combustion of hydrogen is lost as heat rather than doing work
Which of the following represent all of the products of a hydrogen fuel cell?
Water and electricity
How does a fuel cell differ from a battery?
A battery stores electrochemical energy and a fuel cell converts fuel and converts it into electricity
The fuel used in a fuel cell undergoes which type of reaction at the electrode?
Oxidation
What component of a hydrogen fuel cell is reduced?
Oxygen gas
Which of the following is the overall chemical reaction that occurs in a hydrogen fuel cell?
2H2 + O2 → 2H2O
Why is a fuel cell considered a “clean” system?
A fuel cell produces water rather than carbon dioxide or other more noxious gases an exhaust
Which element is the most plentiful in the universe?
Hydrogen
Where is most of the hydrogen gas in the universe is found?
In space as a component of stars and gas clouds
Which of the following regarding hydrogen gas is not true?
Hydrogen is readily available on Earth for use as a fuel
Which of the following statements about the use of hydrogen in fuel cells is true?
Hydrogen is a carrier of energy
Which of the following chemical reactions are important in producing hydrogen gas?
All of these reactions are important in producing hydrogen gas.
