Rechargeable lithium-ion batteries and hydrogen fuel cells can be used to power electric cars.
Complete the balanced equation for the overall reaction in a hydrogen fuel cell
and state what type of reaction it is.

_H2+ _-> _H2O

What pressure will be exerted by 0.675 moles of a gas at 25*c if it is in a 0.750-l container?

Two nitro no2 groups are chemically bonded to a patch of surface. they can't move to another location on the surface, but they can rotate (see sketch at right). it turns out that the amount of rotational kinetic energy each no2 group can have is required to be a multiple of ε, where =ε×1.010−24 j. in other words, each no2 group could have ε of rotational kinetic energy, or 2ε, or 3ε, and so forth — but it cannot have just any old amount of rotational kinetic energy. suppose the total rotational kinetic energy in this system is initially known to be 32ε. then, some heat is removed from the system, and the total rotational kinetic energy falls to 18ε. calculate the change in entropy. round your answer to 3 significant digits, and be sure it has the correct unit symbol.

How do you know when a chemical reaction has occurred