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Flashcards in Acid Base Equilibria Deck (10)
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0

What is the Brönsted Lowry definition of a base?

A proton acceptor
(Can coordinate bond with protons)

1

What is the difference between strong acids and weak acids?

Strong acids donate all of their protons in aq solution whereas weak acids only donate some (in dynamic equilibrium)

2

In the dynamic equilibrium of ethanoic acid, what species(') acts as a base?

H2O in the forward reaction (-> H3O+) and CH3COO- in the backwards reaction

3

What is the definition of pH?

-log[H+(aq)]

Or the concentration of H+(aq) ions in a solution

4

What is Ka measured in?

moldm-3

5

Is Ka big or small with weak acids?

Small- little dissociation occurs

6

In buffer solutions, what happens when you add an acid?

Concentration of H+ increases, so the reversible reaction shifts to the left, removing H+ ions by reaction with Ch3COO-

7

In buffer solutions, what happens when you add a base?

It reacts with H+ ions so their conc decreases
Eq shifts to the right so more H+ are released from the acid

8

When a buffer has equal concentrations of salt an acidic what is [H+] ?

[H+] is equal to the Ka for the acid

9

When calculating the pH of buffers, what do you assume?

That all the salt dissociates but none of the acid dissociates.