Strong and Weak Acids Flashcards
(18 cards)
What can all acids do in solutions?
All acids can ionise (or dissociate) in solution.
What is produced when an acid dissociates in solution?
A hydrogen ion (H+).
e.g.
HCl → H+ + Cl-
How much do strong acids ionise in water?
Strong acids ionise almost completely in water, so a large proportion of the acid molecules dissociate to release H+ ions.
What pHs do strong acids tend to have?
0-2
What are examples of strong acids?
Sulfuric, hydrochloric and nitric acids.
How much do weak acids ionise in solution?
Weak acids do not fully ionise in solution, so only a small proportion of the acid molecules dissociate to release H+ ions.
What pHs do weak acids tend to have?
2-6
What are examples of weak acids?
Ethanoic, citric and carbonic acids.
Is the ionisation of a weak acid reversible?
Yes
If the ionisation of a weak acid is reversible, what does this set up?
The ionisation of a weak acid is reversible, which sets up an equilibrium.
What direction is the equilibrium for the ionisation of a weak acid?
Since only a few of the acid particles release H+ ions, the equilibrium lies well to the left.
What does acid strength tell you?
How strong or weak an acid is - what proportion of the acid molecules ionise in water.
What is the concentration of an acid?
How much acid there is in a litre (1 dm^3) of water.
It is basically how watered down the acid is.
Is an acid with a large number of acid molecules compared to the volume of water concentrated, or dilute?
Concentrated.
Is an acid with a small number of acid molecules compared to the volume of water concentrated, or dilute?
Dilute.
What happens to the pH, if the concentration of H+ ions increases by a factor of 10?
The pH decreases by 1.
What happens to the pH, if the concentration of H+ ions increases by a factor of 100 (10 X 10)?
The pH decreases by 2 (1 + 1).
What happens to the pH, if the concentration of H+ ions decreases by a factor of 10?
The pH increases by 1.
