Question

A) a student measures out initial concentrations of 0.00111 M Fe3+and 0.00424 M SCN-. If the...

A) a student measures out initial concentrations of 0.00111 M Fe3+and 0.00424 M SCN-. If the equilibrium value of Fe(SCN)2+ is found to be 0.00047 M, what is the equilibrium concentrations of Fe3?

B) From a plot of your calibration data, the slope is found to be 11.7. What will be the concentration of your absorbing species in a solution that has an absorbance of 0.372?

C) Using the equilibrium reaction that you are using in your experiment, a student measures out initial concentrations of 0.00151 M Fe3+and 0.00465 M SCN-. If the equilibrium value of Fe(SCN)2+ is found to be 0.00041 M, what is the value of Kc.  

Give all anwers in standard (not scientific) notation.

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Answer #1

Question A.

Fe+3 equilibrium concentration= (0,00111M-X) and X=0,00047M

Fe+3 equilibrium concentration=(0,00111-0,00047)M= 0,00064M

Question B

Beer LAmber Law : A=a.b.c

A=absorbance

a=molar absortivity

b=pathlength

c=concentration

Beer lamber law describes a straight line, Y=m.x

Y=A

m=a.b

X=C

Therefore A=m.C

Question 3

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