Acid and base chemistry Flashcards
What is an Arrhenius acid
Andy substance that produces a H+ in aqueous solution
What is an Arrhenius base
Any substance that produced an OH- in aqueous solution
What is a bronsted lowery acid
A proton donator
What is a bronsted lowery base
A proton acceptor
What is a conjugate base
the substance formed which has lost a proton
What is a conjugate acid
The substance formed which has gained a proton
Definition of amphoteric
A substance which can act as a base and an acid
What is a strong acid
A substance which has a strong tendency to loose a proton
what is a weak acid
A substance that has a weak tendency to loose its protons
What is a Lewis acid
An electron pair acceptor
What is a a Lewis base
an electron pair donator
How to measure ph levels
-log [H+/H3O]
How do you work out the [H+] from [OH-]
Kw=[0H-][H+] —> [H+] = KW/[OH-]
How do you work out the [H+] from [OH-]
Kw=[0H-][H+] —> [H+] = KW/[OH-]
What does pKa suggest
How easily an acid dissociates in solution
What does a low pKa value suggest
Stronger acid
What happens when the ph>pka
The acid exist more as A- than HA
What happens when the ph<pka
The acid exists more as HA and is a weaker acid
How does electronegativity effect a molecules acidity
Higher electronegativity = stronger acid as the stronger bond = more polarity so proton is easily lost
How does a molecules size affect its level of acidity
A larger molecule is more acidic as its bonding electrons are further away from its nucleus so the H+ is more easily lost
What effect does resonance have on a molecules acidity
A molecule with resonance will be a strong acid because the delocalisation will stabilise the conjugate base.
what are acidic buffers
solution that can resist a change in pH when small volume of acid is added
what are acidic buffers made from
a weak acid and its salt
how to acidic buffers work
the weak acid has a high con. of the weak acid but low conc. of its ions and the salt provides a high conc. of its ions but low conc. of the salt. so when an acid is added, the H+ ions bond with the - ion from the salt shifting the equilibrium right creating the weak salt
