Acids and Bases Flashcards
What is a strong acid
One that fully dissociates in water
What is a weak acid
One that partially dissociates in water
Name an example of a strong acid
HCl
HNO3
H2SO4
Acid + Base = ?
Acid + base –> Salt + Water
Acid + Metal = ?
Acid + Metal –> Salt + Hydrogen
Acid + Carbonate = ?
Acid + Carbonate –> Salt + Carbon dioxide + Water
What is the Bronstead Lowry definition of an acid
A proton donator
What is the Bronstead Lowry definition of a base
A proton acceptor
What are the three names of the H3O+ ion
- Hydronium ion
-Hydroxonium ion
-Oxonium ion
How do we work out pH
pH=-log[H+]
How do we work out [H+] using pH
[H+] = 10 ^-pH
How does the concentration of [H+] change as pH decreases
as pH decreases, the concentration of [H+] increases
What does amphoteric mean
Can act as a base / acid
When using Kw, why can you ignore [H2O]
Because it is in extreme excess, so it can be assuemd as almost constant
What is the value of Kw at 298K
1 x 10 ^-14 mol2dm-6
What is the expression for Kw
Kw = [OH-][H+]
What can you assume using Kw for pure water
[OH-] = [H+]
pH + pOH = ?
pH + pOH = 14
When can you use (pH + pOH = 14)
For 298K
Does a bigger Kw value mean more or less dissociation
More dissociation
When do we use Ka
For weak acids
What is the expression for Ka
Ka = [H+][A-] / [HA]
Is dissociation endothermic or exothermic
Endothermic
Always
What will happen when you increase temp to the Ka
- Increase temperarure
- Increase dissociation
- Increase Ka
