You need to be able to get an answer of 2.14 x 10-7 Mfor part c.
A lead ion-selective electrode measured a potential of-33.9 mV when immersed in 50.00 mL of water from a polluted stream.Upon the addition of 0.5mLÂ Â Â Â Â Â Â Â Â of a 0.105mM solution of Pb(NO3)2 the potential changedto -11.2 mV.
a)Â Â Write an equation for the response of thiselectrode, ignoring the response of any other elements (i.e., wewill assume selectivity coefficients for non-lead species are allzero) (4 points).
b) Assuming β = 1 in the above equation, writeexpressions for the response of the electrode to the originalsample and to the spiked sample (6 points).
c) Solve the equations you wrote in (b) to find[Pb2+] in the original sample (6 points).
