# **Analytical Chemistry Atomic Absorption*** Finding the concentration of unknown titanium sample.

label Chemistry
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Mn=internal standard to measure Fe by Atomic Absorption.

ug= micrograms

Standard mixture: 2 ug Mn/mL & 2.50 ug Fe/mL gave quotient (signal?) of 1.05/1.00. A mixture with  a volume of 6 mL was prepared by mixing 5 mL of unknown Fe solutionn w/1 mL containing 13.5 ug Mn/mL.

Absorbance of Mn: 0.128

Absorbance of Fe: 0.185

Find the molarity of the Unknown Fe solution.

May 2nd, 2015

Airon=(Kiron)(Ciron)
Amn=(Kmn)(Cmn)
Airon/Amn= 1.05 = (Kiron)(2.50) / (Kmn)(2.00)

Kiron/Kmn = 0.84

(Kiron)(Ciron) =0.370

(Kmn)(13.5/6)=0.128

Divide the top equation by the bottom one:

2.891 = (Kiron / Kmn)*(Ciron / 2.25) = (0.84)*(Ciron / 2.25)

Ciron(after mixing) = 7.743 mg/L

Ciron(actual) = 7.743*(6/5) = 9.29 mg/L

9.29 mg/L * (1 g / 1000 mg) / (55.8 g/mol) = 1.66 * 10^-4 M

May 2nd, 2015

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May 2nd, 2015
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May 2nd, 2015
Nov 18th, 2017
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