May 04 2010 Today we talked about hydrogen and how it can be
used to power vehicles. Of the forty-four free response
questions on previous A.P. exams, none have addressed hydrogen
power, so Mr. Willard said this would be “good knowledge to have
in our pockets.” First we reviewed what we already knew about
hydrogen. Hydrogen is the most abundant element in the universe.
Despite this fact, there is almost none in the troposphere, and
this is because hydrogen has a very low density and so it rises.
Additionally, hydrogen is very unstable, so it likes to bond
with things (i.e. with oxygen, thus water). In a hydrogen-
powered car, the traditional internal combustion engine is
replaced with a fuel cell. Here is a link to a video we watched
in class about how a fuel cell works: How A Fuel Cell Works:
Inside A Hydrogen-Powered Car
(http://auto.howstuffworks.com/fuel-efficiency/alternative-
fuels/dangerous-hydrogen-fuel1.htm) As with every energy source,
there are pros and cons. The pros to a hydrogen-powered car is
tha