Acids and Bases Flashcards
What are the two aspects of the Bronsted concept
Acids are proton donors (produce H+)
Bases are proton acceptors (use H+)
Water can act as an acid or a base- true/ false
True, water can act as either
What happens when water acts as a base
It accepts a proton forming H3O+
What happens when water acts as an acid
It donates a proton forming OH-
How do you calculate pH
-log[H3O+]
How do you calculate the pH of water
Kw= 10-14
If [H3O+] = [OH-] then [H3O+]= 10-17
pH= -log[10-7]
pH = 7
What is the relationship between H+ and pH
The higher the concentration of H+ the lower the pH
What happens to strong acids and weak bases in water
Strong acids and weak bases almost completely dissociate in water
~100% dissociated
What happens to weak acids and weak bases in water
Weak acids and weak bases are much less dissociated
Calculate the pH for a 0.001M HCl solution
HCl + H2O H3O+ + Cl-
pH = -log[H3O+]
HCl is fully dissociated so [H3O+] from acid = 0.001M
pH = -log(0.001) = 3
Calculate the OH- concentration of a 0.001M HCl solution
Kw = 1x10-14 [H3O+] = 1x10-3 therefore [OH-] = 1x10-14 / 1x10-3 = 1x10-11 moldm-3
What is the pH of a 0.005M solution of NaOH
NaOH fully dissociates so [OH-] = 0.005M
[H30+] = 1x10-14 / 5x10-3
[H3O+] = 2x10-12
pH = -log(2x10-12) = 11.7
What is HCl
A strong acid
What is HI
A strong acid
What is HNO3
A strong acid
