Acids and bases can be described in terms of their ions.Some scientific ideas are unpopular at the beginning.In 1884, a scientist named Svante Arrhenius proposed what at the time was a groundbreaking definition of acids and bases. In his Ph.D. dissertation, Arrhenius, a Swede, proposed that acids and bases could be discussed in terms of the ions that formwhen they are added to water. This hypothesis was not well received by the scientific community. In fact, Arrhenius's professors were so displeased that they gave his dissertation the lowest possible passing score.Arrhenius's problems did not end there. For many years after receiving his Ph.D., Arrhenius met with disrespect for his ideas. He had difficulty finding a teaching job as a result. Later, however, his luck changed, and in 1903 he was awarded the Nobel Prize in Chemistry for his work. This was quite a change of position by the scientific community, and is an example of how science changes as new information becomes available.