Historically, chromium (Cr) has been used in numerous industrial processes, including leather tanning and metal plating operations. In these applications, if the water is mildly acidic, the Cr is typically present as bichromate (HCrO4) and/or dichromate (Cr2O72-) ions. These ions can be interconverted by the reaction: Cr₂O7²- + H₂O The standard Gibbs energies of formation of HCrO4, Cr₂O7², and H₂O are -764.8, -1301, and -237.18 kJ/mol, respectively. Compute the equilibrium constant for the conversion of HCrO4 to Cr₂O7²-. 2HCrO4

Historically, chromium (Cr) has been used in numerous industrial processes, including leather tanning and metal plating operations. In these applications, if the water is mildly acidic, the Cr is typically present as bichromate (HCrO4) and/or dichromate (Cr2O72-) ions. These ions can be interconverted by the reaction: Cr₂O7²- + H₂O The standard Gibbs energies of formation of HCrO4, Cr₂O7², and H₂O are -764.8, -1301, and -237.18 kJ/mol, respectively. Compute the equilibrium constant for the conversion of HCrO4 to Cr₂O7²-. 2HCrO4

Chemistry & Chemical Reactivity

10th Edition

ISBN:9781337399074

Author:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel

Publisher:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel

Chapter18: Principles Of Chemical Reactivity: Entropy And Free Energy

Section: Chapter Questions

Problem 44PS

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The precipitation of Al(OH)3 (Ksp = 1.3 x 10-33) is sometimesused to purify water. (a) Estimate the pH at whichprecipitation of Al(OH)3 will begin if 5.0 lb of Al2(SO4)3is added to 2000 gal of water. (b) Approximately howmany pounds of CaO must be added to the water toachieve this pH?
Consider the Gibbs energies at 25 °C. Substance AG; (kJ · mol-!) Ag*(aq) 77.1 Cl^(aq) -131.2 AgCl(s) -109.8 Br¯(aq) -104.0 AgBr(s) -96.9
The simplest amino acid is glycine, H2NCH2CO2H. The common feature of amino acids is that they contain the functional groups: an amine group, –NH2, and a carboxylic acid group, –CO2H. An amino acid can function aseither an acid or a base. For glycine, the acid strength of the carboxyl group is about the same as that of acetic acid, CH3CO2H, and the base strength of the amino group is slightly greater than that of ammonia, NH3.(a) Write the Lewis structures of the ions that form when glycine is dissolved in 1 M HCl and in 1 M KOH.(b) Write the Lewis structure of glycine when this amino acid is dissolved in water.
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The mixture of 100.0 mL of 0.100 M NaOH (aq) and 100.0 mL of 0.300 M CH3COOH (aq) will result in a buffer. (a) Explain why the resulting solution is a buffer. (b) What is the pH of this buffer?
The thermodynamic solubility product of AGCN is 6.0x10-17. (a) What is [Ag+] in a 0.033 M KNO3 solution? 4.0 7.7e-9 X mol·L-1 (b) What is [Ag+] in a 0.033 M KCN solution? 4.0 1.8e-15 X mol·L-1
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A saturated solution of magnesium hydroxide is prepared and the excess solid magneisum hydorixed is allowed to settle. A 25.0 mL aliquot of the saturated solution is withdrawn and transfered to a flask, two drops of inficator are added. A 0.00053 M HCL is dispensed from a buret into a solution. The solution changes color after the addition of 13.2 mL. What is the molar solubility of magnesium hydroxide?
1) Write the equilibrium constant expression for the following reaction. CaO(S) + 2HCl (aq) <=>CaCl2 (aq) + H2O(l) 2) At 90 C , Kw is about 10-13, what is the pH under these conditions? 3. Will an aqueous solution of NaCl be acidic, neutral or basic?
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