Principles of Instrumental Analysis
7th Edition
ISBN: 9781305577213
Author: Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Question
Chapter 14, Problem 14.21QAP
Interpretation Introduction
Interpretation:
The formation constant for the process
Concept introduction:
The Beer-Lambert Law is:
A − absorbance
l − length of the solution light passes through (cm)
c − concentration of solution (mol/L)
Formation constant is the equilibrium constant for the formation of complex in a solution. This is also known as stability constant.
Expert Solution & Answer
Trending nowThis is a popular solution!
Students have asked these similar questions
The CO stretching vibration frequencies measured in the IR spectra taken in hydrocarbon solutions of co-electron [Mn(CO)6], [Mn(CO)6]- and [Mn(CO)6]+ complexes are 1981, 1859 and 2101 cm-1, respectively. According to these values, the Explain C≡O bond lengths and Mn-C bond lengths
[V(H2O)6]3+, has absorption bands at 17,800 and 25,700 cm-1. Please answer the follow question using a Tanabe-Sugan diagram.
Calculate the values of Δo (octahedral crystal field splitting energy) and B (Racah parameter) in cm-1 if E/B = 31 and Δo /B=31 at the first electronic transition.
A 0.9352g sample of ore containing Fe³+, Al³+ and Sr²+ was dissolved and made up to 500.00 mL. The analysis of metals was performed using complexation volumetry. Initially, an aliquot of 50.00 mL had its pH adjusted to 1.0 and titrated with a standard 0.03145 mol/L EDTA solution, requiring 6.95 mL to reach the end point. Subsequently, another 25.00 mL aliquot was buffered at pH=5 and titrated with the same EDTA solution, requiring 6.24 mL to reach the end point. Finally, a third aliquot of 25.00 mL was titrated at pH=11, requiring 11.10 mL of the same EDTA solution to complete the titration.
Given the molar masses: Fe=55.845 g/mol; Al-26.982 g/mol and Sr-87.620 g/mol.
a) Determine the percentage of each of the metals in the sample.
b) Explain why the change in pH allows the determination of the three ions in this sample.
Chapter 14 Solutions
Principles of Instrumental Analysis
Ch. 14 - Prob. 14.1QAPCh. 14 - A 0.4740-g pesticide sample was decomposed by wet...Ch. 14 - Sketch a photometric titration curve for the...Ch. 14 - Prob. 14.4QAPCh. 14 - Prob. 14.5QAPCh. 14 - The accompanying data (1.00-cm cells) were...Ch. 14 - A 3.03-g petroleum specimen was decomposed by wet...Ch. 14 - Prob. 14.8QAPCh. 14 - Prob. 14.9QAPCh. 14 - The acid-base indicator HIn undergoes the...
Ch. 14 - Prob. 14.11QAPCh. 14 - Prob. 14.12QAPCh. 14 - Copper(II) forms a 1:1 complex with the organic...Ch. 14 - Aluminum forms a 1:1 complex with...Ch. 14 - Prob. 14.15QAPCh. 14 - Prob. 14.16QAPCh. 14 - Prob. 14.17QAPCh. 14 - Prob. 14.18QAPCh. 14 - Prob. 14.19QAPCh. 14 - Given the Information that...Ch. 14 - Prob. 14.21QAPCh. 14 - Mixing the chelating reagent B with Ni(II) forms...Ch. 14 - Prob. 14.23QAP
Knowledge Booster
Similar questions
- Ammonium iron(II) sulfate crystals have the following formula: (NH4)2SO4.FeSO4.nH2O . In an experiment to determine n 8.492g of the salt were dissolved and made up to 250cm^-3 of solution with distilled water and sulphuric acid. A 25.0cm^-3 portion of the solution was titrated against 0.0150 mol dm^-3 KMnO4. A volume of 22.5cm^-3 was required. Find the value of narrow_forwardA 1.000-g sample containing bromide was dissolved in sufficient water to give 100.0 mL. A 50.00 mL aliquot was measured and after acidification, silver nitrate was introduced to precipitate AgBr, which was filtered, washed, and then dissolved in an ammoniacal solution of potassium tetracyanonickelate(II): Ni(CN)42- + 2AgBr(s) → 2Ag(CN)2- + Ni2+ + 2Br-50.00 mL remaining solution was analyzed for its Br- content by potentiometry using a metallic electrode of the second kind. a) Write the cell notation of the potentiometric set-up with SCE as the reference electrode. b) Write the Nernst equation that describes the indicator electrode set-up. Ecell recorded in running the solution using the potentiometric set-up was Ecell = 0.0286 V. (E0Ag/AgBr = 0.095 V) c) Compute for Eind. d) Compute pBr in the 50.00 mL aliquot. e) Compute for % NaBr ( in the potentiometric technique).arrow_forwardThe CO stretching vibration frequencies measured in the IR spectra taken in hydrocarbon solutions of co-electron [Mn(CO)6], [Mn(CO)6]- and [Mn(CO)6]+ complexes are 1981, 1859 and 2101 cm-1, respectively. According to these values, compare the C≡O bond lengths in the complexes by explaining the Mn-C bond lengths.arrow_forward
- The absorbance of a 0.00105% m/v solution of tolbutamide in methanol when measured in a 1 cm path length cell was found to be 0.796 at 228 nm. Calculate the specific absorbance.arrow_forwardA solution containing the complex formed between Bi(III) and thiourea has a molar absorptivity of 9.32 x 103 M-1 cm-1 at 470 nm. (a) Calculate the absorption of a 4.25x10-5 M solution of the complex at 470 nm in a 1-cm cell. (b) What is the molar concentration of the complex in a solution that has the calculated absorption in (a) when measured at 470 nm in a 2.50 cm cell?arrow_forwardThe observed absorption band of the M2 + ion in the electronic spectrum of the hexaakua complex is 7500 cm-1. How many kJ / mol is the crystal field cleavage of the tetraakua complex of the same ion? (h = 6,626x10-34Js, c = 3x108ms-1) A. 142.63 B. 25.95 C. 2698.56 D. 39.88 E. 3333.33arrow_forward
- You wish to measure the iron content of the well water on the new property you are about to buy. You prepare a reference standard Fe3+ solution with a concentration of 5.53×10−4 M. You treat 10.0 mL of this reference with HNO3 and excess KSCN to form a red complex and dilute the reference to 45.0 mL. The diluted reference is placed in a cell with a 1.00‑cm light path. You then take 20.0 mL of the well water, treat with HNO3 and excess KSCN, and dilute to 100.0 mL. This diluted sample is placed in a variable pathlength cell. The absorbance of the reference and the sample solutions match when the pathlength is 3.25cm. What is the concentration of iron in the well water? For each solution, the zero is set with a blank.arrow_forwardMixing the chelating reagent B with Ni(II) forms the highly colored NiB22+, whose solutions obey Beer’s lawat 395 nm overa wide range. Provided the analytical concentration of the chelating reagent exceeds that of Ni(II) by a factor of 5 (or more), the cation exists, within the limits of observation, entirely in the form of the complex. Use the accompanying data to evaluate the formation constant Kf for the process Ni2++2BNiB22+arrow_forwardThe accompanying data (1.00-cm cells) were obtained for the spectrophotometric titration 10.00 mL of Pd(II) with 2.44 10-4 M Nitroso R(O. W Rollins and M. M. Oldham, Anal. chem .,1971, 43, 262, DOI: 10.1021/ac60297a026). Calculate the concentration of the Pd(II) solution, given that the ligand-to-cation ratio in the colored product is 2:1arrow_forward
- In the determination of iron in fortified cereals by atomic absorption, 0.9133 g of sample was weighed. After a previous treatment, it was dissolved and diluted to 100 mL, an aliquot of 25.0 mL was taken, this was diluted to 100 mL and this solution presented an absorbance reading of 0.251. A series of iron standards of the following concentrations were prepared: 0.0; 1.0; 2.0; 2.5 and 3.0 ppm. Whose absorbances were 0.0; 0.241; 0.405; 0.520 and 0.640. Determine the iron concentration in mg/100 g of sample.arrow_forwardThe wavelength of maximum absorption of the complex FeSCN^(2+) has a molar absorptivity of 6.99 x 10^3 L(cm^-1)(mol^-1) at 580 nm a. Calculate the ABSORBANCE of a 2.65 x 10^-5 M solution of the complex at this wavelength using a 1.5 cm cell. b. Calculate the ABSORBANCE of the solution in which the concentration of the complex is twice that in (1)arrow_forwardYou wish to measure the iron content of the well water on the new property you are about to buy. You prepare a reference standard Fe3+ solution with a concentration of 5.74×10−4 M. You treat 14.0 mL of this reference with HNO3 and excess KSCN to form a red complex and dilute the reference to 60.0 mL. The diluted reference is placed in a cell with a 1.00‑cm light path. You then take 30.0 mL of the well water, treat with HNO3 and excess KSCN, and dilute to 100.0 mL. This diluted sample is placed in a variable pathlength cell. The absorbance of the reference and the sample solutions match when the pathlength is 1.76 cm. What is the concentration of iron in the well water? For each solution, the zero is set with a blank.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Principles of Instrumental AnalysisChemistryISBN:9781305577213Author:Douglas A. Skoog, F. James Holler, Stanley R. CrouchPublisher:Cengage Learning
Principles of Instrumental Analysis
Chemistry
ISBN:9781305577213
Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher:Cengage Learning