Introduction to Acid and Base reactions

Read the article you find in this Link
WikiChem Acid / Base Basics
and answer:

• Where do acids and bases normally exist?
• Tell four properties of each susbstance people knew
• Who was Arrhenius? When and where dis he live?
•  How did Arrhenius define an acid or a base?
• Why do they say that free hydrogen ions cannot exist into water?
• Explain several limitations of the Arrhenius theory?
• Which other theories exist to explain acid and bases?
• How do they explain acids and bases?