All Matches

Solution Library

Expert Answer

Textbooks

Search Textbook questions, tutors and Books

Oops, something went wrong!

Change your search query and then try again

Result Not Found

Books FREE
Tutors
Study Help
Ask a Question

Search
Sign In
Register

study help
engineering
chemical engineering

Questions and Answers of Chemical Engineering

Find the pH and the concentration of each species of lysine in a solution of 0.0100 M lysine HCl, lysine monohydrochloride.
How many milliliters of 1.00 M KOH should be added to 100 mL of solution containing 10.0 g of histidine hydrochloride (His HCl,FM 191.62) to get a pH of 9.30?
(a)Using activity coefficients, calculate the pH of a solution containing a 2.00:1.00 mole ratio of HC2-:C3- (H3C = citric acid). The ionic strength is 0.010 M. (b) What will be the pH if the ionic
The acid HA has pKa = 7.00. (a) Which is the principal species, HA or A-, at pH 6.00? (b) Which is the principal species at pH 8.00? (c) What is the quotient [A-]/[HA] at pH 7.00? at pH 6.00?
The diprotic acid H2A has pK1 = 4.00 and pK2 = 8.00. (a) At what pH is [H2A] = [HA-]? (b) At what pH is [HA-] = [A2-]? (c) Which is the principal species at pH 2.00: H2A, HA-, or A2-? (d) Which is
The base B has pKb = 5.00. (a) What is the value of pKa for the acid BH+? (b) At what pH is [BH+] = [B]? (c) Which is the principal species at pH 7.00: B or BH+? (d) What is the quotient [B]/[BH+] at
The acid HA has pKa = 4.00. Use Equations 9-17 and 9-18 to find the fraction in the form HA and the fraction in the form A- at pH = 5.00. Does your answer agree with what you expect for the quotient
A dibasic compound, B, has pKb1 = 4.00 and pKb2 = 6.00. Find the fraction in the form BH2 2+ at pH 7.00, using Equation 9 - 19. Note that K1 and K2 in Equation 9-19 are acid dissociation constants
Write the chemical reactions whose equilibrium constants are Kb1 and Kb2 for the amino acid proline. Find the values of Kb1 and Kb2.
What fraction of ethane-1,2-dithiol is in each form (H2A, HA-, A2-) at pH 8.00? at pH 10.00?
(a) Derive equations for ,αH2A, αH2A-, and αA2- for a triprotic system.(b) Calculate the values of these fractions for phosphoric acid at pH 7.00.
A solution containing acetic acid, oxalic acid, ammonia, and pyridine has a pH of 9.00. What fraction of ammonia is not protonated?
A solution was prepared from 10.0 mL of 0.100 M cacodylic acid and 10.0 mL of 0.0800 M NaOH. To this mixture was added 1.00 mL of 1.27 × 10-6 M morphine. Calling morphine B, calculate the fraction
Fractional composition in a tetraprotic system. Prepare a fractional composition diagram analogous to Figure 9-4 for the tetraprotic system derived from hydrolysis of Cr3+:Cr3+ + (H2O) ⇌ Cr(OH)2+ +
What is the difference between the isoelectric pH and the isoionic pH of a protein with many different acidic and basic substituents?
Consider the diprotic acid H2A with K1 = 1.00 × 10-4 and K2 = 1.00 × 10-8. Find the pH and concentrations of H2A, HA-, and A2- in (a) 0.100 M H2A; (b) 0.100 M NaHA; (c) 0.100 M Na2A.
Calculate the isoelectric and isoionic pH of 0.010 M threonine.
Explain how isoelectric focusing works.
We will abbreviate malonic acid, CH2(CO2H)2, as H2M. Find the pH and concentrations of H2M, HM-, and M2- in (a) 0.100 M H2M; (b) 0.100 M NaHM; (c) 0.100 M Na2M.
Calculate the pH of 0.300 M piperazine. Calculate the concentration of each form of piperazine in this solution.
Use the method of Box 9-2 to calculate the concentrations of H+, H2A, HA-, and A2- in 0.00100 M monosodium oxalate, NaHA.
Activity. In this problem, we calculate the pH of the intermediate form of a diprotic acid, taking activities into account.(a) Including activity coefficients, derive Equation 9-11 for potassium
Use the method in Box 9-2 to find the pH and concentration of HA- in a 0.01 F solution of the amphiprotic salt Na+ HA- derived from the diprotic acid H2A with pK1 = 4 and (a) pK2 = 8 or (b) pK2 =
Distinguish the terms end point and equivalence point.
Use activity coefficients to calculate the pH after 10.0 mL of 0.100 M trimethylammonium bromide were titrated with 4.0 mL of 0.100 M NaOH.
Sketch the general appearance of the curve for the titration of a weak base with a strong acid. Explain (in words) what chemistry governs the pH in each of the four distinct regions of the curve.
A 100.0-mL aliquot of 0.100 M weak base B (pKb = 5.00) was titrated with 1.00 M HClO4. Find the pH at the following volumes of acid added and make a graph of pH versus Va: Va 0, 1, 5, 9, 9.9, 10,
At what point in the titration of a weak base with a strong acid is the maximum buffer capacity reached? This is the point at which a given small addition of acid causes the least pH change.
What is the equilibrium constant for the reaction between benzylamine and HCl?
A 50.0-mL solution of 0.0319 M benzylamine was titrated with 0.0500 M HCl. Calculate the pH at the following volumes of added acid: Va = 0,12.0, ½ Ve 30.0, Ve, and 35.0 mL.
Calculate the pH of a solution made by mixing 50.00 mL of 0.100 M NaCN with (a) 4.20 mL of 0.438 M HClO4 (b) 11.82 mL of 0.438 M HClO4 (c) What is the pH at the equivalence point with 0.438 M HClO4?
Sketch the general appearance of the curve for the titration of a weak diprotic acid with NaOH. Explain (in words) what chemistry governs the pH in each distinct region of the curve.
Consider the titration of 100.0 mL of 0.100 M NaOH with 1.00 M HBr. Find the pH at the following volumes of acid added and make a graph of pH versus Va: Va = 0, 1, 5, 9, 9.9, 10, 10.1, and 12 mL.
The opening page of this chapter shows the titration curve for an enzyme. Is the average charge of the protein positive, negative, or neutral at its isoionic point? How do you know?
The base NaA, whose anion is dibasic, was titrated with HCl to give curve b in Figure 10-4. Is the first equivalence point (H) the isoelectric point or the isoionic point?
The figure compares the titration of a monoprotic weak acid with a monoprotic weak base and the titration of a diprotic acid with strong base.(a) Write the reaction between the weak acid and the weak
The dibasic compound B (pKb1 = 4.00, pKb2 8.00) was titrated with 1.00 M HCl. The initial solution of B was 0.100 M and had a volume of 100.0 mL. Find the pH at the following volumes of acid added
A 100.0-mL aliquot of 0.100 M diprotic acid H2A (pK1 4.00, pK2 8.00) was titrated with 1.00 M NaOH. Find the pH at the following volumes of base added and make a graph of pH versus Vb: Vb 0, 1, 5,
Calculate the pH at 10.0-mL intervals (from 0 to 100 mL) in the titration of 40.0 mL of 0.100 M piperazine with 0.100 M HCl. Make a graph of pH versus Va.
Consider the titration of 50.0 mL of 0.100 M sodium glycinate, H2NCH2CO2Na, with 0.100 M HCl.(a) Calculate the pH at the second equivalence point.(b) Show that our approximate method of calculations
A solution containing 0.100 M glutamic acid (the molecule with no net charge) was titrated to its first equivalence point with 0.0250 M RbOH.(a) Draw the structures of reactants and products.(b)
Find the pH of the solution when 0.010 0 M tyrosine is titrated to the equivalence point with 0.00400 M HClO4.
Why does an acid-base titration curve (pH versus volume of titrant) have an abrupt change at the equivalence point?
This problem deals with the amino acid cysteine, which we will abbreviate H2C.
How many grams of dipotassium oxalate (FM 166.22) should be added to 20.0 mL of 0.800 M HClO4 to give a pH of 4.40 when the solution is diluted to 500 mL?
When 5.00 mL of 0.1032 M NaOH were added to 0.1123 g of alanine (FM 89.093) in 100.0 mL of 0.10 M KNO3, the measured pH was 9.57. Use activity coefficients to find pK2 for alanine. Consider the ionic
Data for the titration of 100.00 mL of a weak acid by NaOH are given below. Find the end point by preparing a Gran plot, using the last 10% of the volume prior to Ve.
Prepare a second derivative graph to find the end point from the following titration data.
Why does a properly chosen indicator change color near the equivalence point in a titration?
The pH of microscopic vesicles (compartments) in living cells can be estimated by infusing an indicator (HIn) into the compartment and measuring the quotient [In-]/[HIn] from the spectrum of the
Sketch the general appearance of the curve for the titration of a weak acid with a strong base. Explain (in words) what chemistry governs the pH in each of the four distinct regions of the curve.
(a) What is the pH at the equivalence point when 0.030 0 M NaF is titrated with 0.0600 M HClO4? (b) Why would an indicator end point probably not be useful in this titration?
A titration curve for NaCO3 titrated with HCl is shown here. Suppose that both phenolphthalein and bromocresol green are present in the titration solution. State what colors you expect to observe at
In the Kjeldahl nitrogen determination, the final product is a solution of NH4 in HCl solution. It is necessary to titrate the HCl without titrating NH4.a. Calculate the pH of pure 0.010 M NH4Cl.b.
A 10.231-g sample of window cleaner containing ammonia was diluted with 39.466 g of water. Then 4.373 g of solution were titrated with 14.22 mL of 0.1063 M HCl to reach a bromocresol green end point.
A procedure to measure the alkalinity (Box 10-1) of home swimming pool water is to titrate a fixed volume of pool water by counting the number of drops of standard H2SO4 to reach the bromocresol
Give the name and formula of a primary standard used to standardize (a) HCl and (b) NaOH.
A solution was prepared from 1.023 g of the primary standard tris (Table 10 - 4) plus 99.367 g of water; 4.963 g of the solution were titrated with 5.262 g of aqueous HNO3 to reach the methyl red end
A solution was prepared from 1.023 g of the primary standard tris (Table 10 - 4) plus 99.367 g of water; 4.963 g of the solution were titrated with 5.262g of aqueous HNO3 to reach the methyl red end
The balance says that you have weighed out 1.023 g of tris to standardize a solution of HCl. Use the buoyancy correction in Section 2-3 and the density in Table 10-4 to determine how many grams you
A solution was prepared by dissolving 0.1947 g of HgO (Table 10-4) in 20 mL of water containing 4 g of KBr. Titration with HCl required 17.98 mL to reach a phenolphthalein end point. Calculate the
Constant-boiling aqueous HCl can be used as a primary standard for acid-base titrations. When ~20 wt% HCl (FM 36.461) is distilled, the composition of the distillate varies in a regular manner with
(a) Uncertainty in formula mass. In an extremely-high-precision gravimetric titration, the uncertainty in formula mass of the primary standard could contribute to the uncertainty of the result.
The Kjeldahl procedure was used to analyze 256 μL of a solution containing 37.9 mg protein/mL. The liberated NH3 was collected in 5.00 mL of 0.0336 M HCl, and the remaining acid required 6.34 mL of
What is meant by the leveling effect?
A weak acid HA (pKa 5.00) was titrated with 1.00 M KOH. The acid solution had a volume of 100.0 mL and a molarity of 0.100 M. Find the pH at the following volumes of base added and make a graph of pH
Considering the following pKa values,31 explain why dilute sodium methoxide (NaOCH3) and sodium ethoxide (NaOCH2CH3) are leveled to the same base strength in aqueous solution. Write the chemical
The base B is too weak to titrate in aqueous solution.(a) Which solvent, pyridine or acetic acid, would be more suitable for the titration of B with HClO4? Why?(b) Which solvent would be more
Explain why sodium amide (NaNH2) and phenyl lithium (C6H5Li) are leveled to the same base strength in aqueous solution. Write the chemical reactions that occur when these reagents are added to water.
Pyridine is half protonated in aqueous phosphate buffer at pH 5.2. If you mix 45 mL of phosphate buffer with 55 mL of methanol, the buffer must have a pH of 3.2 to half protonate pyridine. Suggest a
Derive the following equation for the titration of potassium hydrogen phthalate (KHP) with NaOH:
Effect of pKb in the titration of weak base with strong acid. Using the appropriate equation in Table 10 - 5, compute and plot a family of curves analogous to the left part of Figure 10 -3 for the
(a) Prepare a family of graphs for the titration of 50.0 mL of 0.0200 M HA (pKa 4.00) with 0.100 M B (pKb = 3.00, 6.00, and 9.00).(b) Write the acid-base reaction that occurs when acetic acid and
Prepare a family of graphs for the titration of 50.0 mL of 0.0200 M H2A with 0.100 M NaOH. Consider the following cases: (a) pK1 = 4.00, pK2 8.00; (b) pK1 = 4.00, pK2 = 6.00; (c) pK1 = 4.00, pK2
Consider the titration of the weak acid HA with NaOH. At what fraction of Ve does pH = pKa - 1? At what fraction of Ve does pH pKa - 1? Use these two points, plus Ve, and 1.2Ve to sketch the
Prepare a spreadsheet to reproduce the lower curve in Figure 10-4.
Prepare a spreadsheet to graph the titration of 50.0 mL of 0.0200 M histidine 2HCl with 0.100 M NaOH. Treat histidine 2HCl with the triproticacid equation in Table 10-5.
Write an equation for the titration of tetrabasic base with strong acid (B + H+ → → → → BH4+4. You can do this by inspection of Table 10-5 or you can derive it from the charge balance for the
Spectrophotometric properties of a particular indicator are given below:
A certain acid-base indicator exists in three colored forms:
What is the pH at the equivalence point when 0.100 M hydroxyacetic acid is titrated with 0.0500 M KOH?
Calculate [HY3-] in a solution prepared by mixing 10.00 mL of 0.010 0 M VOSO4, 9.90 mL of 0.010 0 M EDTA, and 10.0 mL of buffer with a pH of 4.00.
Use Equation 11-11 to compute curves (pM versus mL of EDTA added) for the titration of 10.00 mL of 1.00 mM M2+ (= Cd2+ or Cu2+) with 10.0 mM EDTA at pH 5.00. Plot both curves on one graph.
Use Equation 11-11 to compute curves (pCa2+ versus mL of EDTA added) for the titration of 10.00 mL of 1.00 mM Ca2+ with 1.00 mM EDTA at pH 5.00, 6.00, 7.00, 8.00, and 9.00. Plot all curves on one
Use Equation 11-12 to reproduce the results of Exercise 11-C.
State the purpose of an auxiliary complexing agent and give an example of its use.
According to Appendix I, Cu2 forms two complexes with acetate:(a) Referring to Box 6-2, find K2 for the reactionCu(CH3CO2) + CH3CO-2 ‡Œ Cu(CH3CO2)2(aq)K2
Calculate pCu2 at each of the following points in the titration of 50.00 mL of 0.001 00 M Cu2 with 0.001 00 M EDTA at pH 11.00 in a solution with [NH3] fixed at 1.00 M:(a) 0 mL (b) 1.00 mL (c)
Consider the derivation of the fraction Î±M in Equation 11-16.(a) Derive the following expressions for the fractions Î±ML. And Î±ML2(b) Calculate the values of
Microequilibrium constants for binding of metal to a protein. The iron-transport protein, transferrin, has two distinguishable metal-binding sites, designated a and b. The microequilibrium formation
Spreadsheet equation for auxiliary complexing agent. Consider the titration of metal M (initial concentration CM, initial volume VM) with EDTA (concentration CEDTA, volume added VEDTA) in the
State (in words) what α γ 4-means. Calculate for EDTA at α γ4- (a) pH 3.50 and (b) pH 10.50.
Use the equation derived in Problem 11-19.(a) Prepare a spreadsheet to reproduce the 20-, 50-, and 60-mL points in the EDTA titration of Zn2+ in the presence of NH3 in the example on pages
Consider the titration of metal M (initial concentration = CM, initial volume = VM) with ligand L (concentration = CL, volume added = VL), which can form 1:1 and 2:1 complexes:Let Î±M be
Use the equation from Problem 11-21, where M is Cu2+ and L is acetate. Consider adding 0.500 M acetate to 10.00 mL of 0.050 0 M Cu2+ at pH 7.00 (so that all ligand is present as CH3CO2- , not
Explain why the change from red to blue in Reaction 11-19 occurs suddenly at the equivalence point instead of gradually throughout the entire titration.
Describe what is done in a displacement titration and give an example.
Give an example of the use of a masking agent.
(a) Find the conditional formation constant for Mg(EDTA)2- at pH 9.00.(b) Find the concentration of free Mg2+ in 0.050 M Na2[Mg(EDTA)] at pH 9.00.
What is meant by water hardness? Explain the difference between temporary and permanent hardness.

Showing 5200 - 5300 of 6781

First
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Last

Get In Touch

About Us
Contact Us
Career
Jobs
FAQ
Campus Ambassador

Company Info

Security
Copyrights
Privacy Policy
Terms & Condition
SolutionInn Fee
Scholarship

Services

Sitemap
Fun
Definitions
Become Tutor
Study Help Categories
Recent Questions
Expert Questions

Copyright © 2024 SolutionInn All Rights Reserved.

Get the SolutionInn - Study Help App