How do you answer a long answer question on how buffer systems work?

1) First, state how the buffer is prepared by saying that an excess of acid reacts with a base (include the equation for this reaction)

b) Write the overall equation of the buffer system (remember to show it as reversible) 

c) State the effect of adding an acid to the mixture: there is an increase in H+ concentration, this reacts with the conjugate base and equilibrium shifts left

d) State the effect of adding an alkali: it reacts with H+ ions leading to a fall in H+ conc, equilibrium shifts to right to restore concentrations

n.b the Ka of the buffer system remains the same throughout all the concentration changes 

RS

Related Chemistry A Level answers

All answers ▸

Consider the following reaction: C2H4 + HBr -> ?. a) What is the product of the reaction? Name the compound and give the structural formula. b) What is the type of the reaction? c) Draw a reaction mechanism.


Why are zinc and Scandium not transition metals?


(i) What property does Magnesium Oxide have that makes it useful to create heat-resistant bricks to line furnaces? (ii) Explain why H2S exists as a gas and H2O exists as a liquid (at r.t.p).


What is the trend in electronegativity of group 7?