The following data were obtained when a Ca2+ ion selective electrode was immersed in a series of standard solutions.
Ca2+ (M)
3.38E-5
3.38E-3
3.38E-1
E(mV)
-74.8
-18.7
37.7
Calculate the concentration of a sample that gave a reading of -22.5 mV
4 answers
I suggest you plot the data, then read concn from the graph at -22.5 mV.
Did that multiple times and the answer is still incorrect. The equation I computed was y=252.346x+(-47.318)
I've also tried plugging in -22.5 as y and solved for x and still got .098M which was incorrect
I've also tried plugging in -22.5 as y and solved for x and still got .098M which was incorrect
Just a glimmer of hope here but it might be worth trying. You data has three significant figures and your answer only two; these on-line data bases are notorious about s.f. Try adding another place to your answer.
the correct answer is 2.45E-3M but I have no clue how that's possible
2 answers