11 May Exam Flashcards
If they ask you why to keep methane etc?
Because it can be used as fuel for combustion.
What is the name of X nitrate etc?
You will ALWAYS have to put down the oxidation state.
What is the oxidation number of H in a metal hydride
Always -1.
Neutralisation Enthalpy note
It is always negative!!!
Why is another fuel better than hydrogen?
The other fuel is a liquid and easier to store.
Hydrogen is also explosive.
The other fuel has a greater cell potential.
One important difference between a fuel cell and a conventional electrochemical cell
A fuel cell converts energy from a reaction of a fuel with oxygen into voltage.
Write the overall equation that takes place in a hydrogen fuel cell.
2H2 + O2 -> 2H20.
State how hydrogen can be stored as a fuel for cars
Under pressure, at low temperature.
Adsorbed on solid.
Absorbed within solid.
Why do some think that the hydrogen fueled cars consume more energy than fossil fuels, such as petrol
Because energy is needed to make the hydrogen.
Whenever writing the oxidation half equation(or reduction)-
Make sure that you multiply the change in electron by the number of atoms that have a change in oxidation state.
