What is the difference between strong acid and weak acid

Strong acids dissociate completely. What does it mean? If a strong acid is put into water, it will break completely into H+ and whatever it left (for example HCl --> H+ and Cl-). So if I start with 3 moles of HCl , it will break and give 3 moles of H+ and 3 moles of Cl-.

A weak acid, on the other hand, dissociates only partially. For example, if I start out with 3 moles of acetic acid, only 0.002 moles of it will break down and create H+.

How can you distinguish between strong and weak acids?

Just memorize the strong ones and if your acid is not strong, it must be weak.

Strong acids: hydrochloric acid (HCl), hydroiodic acid (HI), hydrobromic acid (HBr), perchloric acid (HClO4), nitric acid (HNO3) and sulphuric acid (H2SO4).

To speak to the best chemistry tutor in NYC or only, please contact us here


Featured Posts