what is the difference between acids and bases?

Answer 1

there are many diferences:
1)acid turns litmus paper blue to red while base turns litmus from red to blue
2)acids produce H+ ions in aqueous solutions
bases produce OH- ions in aqueous solutions
3)acids are proton donors
bases are proton acceptors

Answer 2

In a neutral solution (neither acid nor base) like pure water, there are an equal number of hydrogen (H+) and hydroxide (OH-) ions. This is because the water molecules (HOH) are continually breaking down and the ions recombining. This state is called equilibrium which means balance. Acids or bases upset that equilibrium one way or the other. Acids by definition are substances which, when added to water increase the number of free hydrogen ions (H+). These hydrogen ions immediately attach themselves to polar water molecules to form hydronium ions (H30+). As others have mentioned the excess of hydrogen ions lower the pH of the solution, turn litmus paper red and cause the solution to taste sour (think lemon juice). The word "acid" comes from the Latin word for sharp and was so named because of this sour taste. Bases on the other hand upset the equilibrium the opposite way. When dissolved in water they result in an increase of hydroxide ions (OH-). These ions increase the pH of the solution causing litmus paper dipped in it to turn blue and cause the solution to taste bitter (think baking soda).

Answer 3

Acids are protonated with Hydrogens and usually want to get rid of the protons to become more stable. Consequently, bases have a negative charge and want to pick up positive protons to become more stable.

Answer 4

bronsted says acid is a H donor, and a base is a H acceptor