Question 15 Consider an indicator for which K 1.0 x 101, and that ionizes as follows: l(aq) + H2(e) = H₂+(aq) - Yellow + In Red -(aq) Which of the following statements is true? (i) The predominant. colour in acid solution is yellow. (ii) In the middle of the pH range of its colour change, a solution containing the indicator will probably be orange. (iii) At pH 8, most of the indicator is present in the un-ionised form. (iv) The indicator changes colour at a pll of 4. (y) The indicator can be used for the titration of a strong acid with a strong base. A (i), (iii), (v) C (ii), (iv), (v) E (i), (ii), (iii), (v) B (i), (ii), (iv) D (i), (iv), (v) F (i), (ii), (v) 3

Question 15 Consider an indicator for which K 1.0 x 101, and that ionizes as follows: l(aq) + H2(e) = H₂+(aq) - Yellow + In Red -(aq) Which of the following statements is true? (i) The predominant. colour in acid solution is yellow. (ii) In the middle of the pH range of its colour change, a solution containing the indicator will probably be orange. (iii) At pH 8, most of the indicator is present in the un-ionised form. (iv) The indicator changes colour at a pll of 4. (y) The indicator can be used for the titration of a strong acid with a strong base. A (i), (iii), (v) C (ii), (iv), (v) E (i), (ii), (iii), (v) B (i), (ii), (iv) D (i), (iv), (v) F (i), (ii), (v) 3

Chemistry by OpenStax (2015-05-04)

1st Edition

ISBN:9781938168390

Author:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark Blaser

Publisher:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark Blaser

Chapter15: Equilibria Of Other Reaction Classes

Section: Chapter Questions

Problem 76E: Write the Lewis structures of the reactants and product of each of the following equations, and...

See similar textbooks

Similar questions

. How is the strength of an acid related to the fact that a competition for protons exists in aqueous solution between water molecules and the anion of the acid?
You have a solution of the weak acid HA and add some of the salt NaA to it. What are the major species in the solution? What do you need to know to calculate the pH of the solution, and how would you use this information? How does the pH of the solution of just the HA compare with that of the final mixture? Explain.
Calculate the pH of a buffer solution prepared from 0.155 mol of phosphoric acid, 0.250 mole of KH2PO4, and enough water to make 0.500 L of solution.
Sketch a titration curve for the titration of potassium hydroxide with HCl, both 0.100 M. Identify three regions in which a particular chemical species or system dominates the acid-base equilibria.
A buffer is prepared in which the ratio [ H2PO4 ]/[ HPO42 ]is 3.0. (a) What is the pH of this buffer? (b) Enough strong acid is added to convert 15% of HPO42- to H2PO4-. What is the pH of the resulting solution? (c) Enough strong base is added to make the pH 7.00. What is the ratio of [H2PO4-] to [HPO42-] at this point?
Amino acids are an important group of compounds. At low pH, both the carboxylic acid group (CO2H) and the amine group (NHR) are protonated. However, as the pH of the solution increases (say, by adding base), the carboxylic acid proton is removed, usually at a pH between 2 and 3. In a middle range of pHs, therefore, the amine group is protonated, but the carboxylic acid group has lost the proton. (This is called a zwitterion.) At more basic pH values, the amine proton is dissociated. What is the pH of a 0.20 M solution of alanine hydrochloride, [NH3CHCH3CO2H]Cl?
Isocyanic acid (HNCO) can be prepared by heating sodium cyanate in the presence of solid oxalic acid according to the equation 2NaOCN(s)+H2C2O4(s)2HNCO(l)+Na2C2O4(s) Upon isolating pure HNCO(l), an aqueous solution of HNCO can be prepared by dissolving the liquid HNCO in water. What is the pH of a l00.-mL solution of HNCO prepared from the reaction of 10.0 g each of NaOCN and H2C2O4, assuming all of the HNCO produced is dissolved in solution? (Ka of HNCO = 1.2 l04.)
Addition of the indicator methyl orange to an unknownsolution leads to a yellow color. The addition of bromthymolblue to the same solution also leads to a yellow color.(a) Is the solution acidic, neutral, or basic? (b) What is therange (in whole numbers) of possible pH values for the solution?(c) Is there another indicator you could use to narrowthe range of possible pH values for the solution?
B represents an acid-base indicator and behaves like a base. Its dissociation equilibrium in an aqueous solution can be written as: B(ac) + H2O(l) <-> +BH(ac) + OH(ac) If B (ac) is yellow +BH is red. Using Le Châtelier's principle, predict the color of the indicator by adding a few drops of the indicator to an aqueous solution of HCl and an aqueous solution of NaOH. Write the corresponding chemical reactions.
If the pH of a 0.200 M solution of the CICH2O¯ ion is 12.05, then what is the value for the basicity constant, Kp, of CICH20-? You do not need to make a simplifying assumption CICH,0-(aq) + H2O(1) СICH-OОH(aq) + ОН (аq) K½ = ?
Determine the pH of the resulting solution when the following two solutions are mixed: 50.0 mL of 0.500M HNO. and 30.0 mL of 0.200 M Ca(OH)2. The value of Ka for HNO: is 6.8 x 104. 1 2 3 4 NEXT > Use the table below to determine the moles of reactant and product after the reaction of the acid and base. You can ignore the amount of liquid water in the reaction. HNO2(aq) OH (aq) H2O(1) NO: (aq) + + Before (mol) Change (mol) After (mol)
The acid dissociation constants for sulfurous acid are: Ka1 3D 1.2 х 10-2 and Ka2 - 6.6 х 10-8 (a) Calculate the pH of a solution of 0.10 M H2SO3. (b) Calculate the pH of a solution of 0.10 M Na2SO3. (c) Calculate the pH of the solution resulting when equal volumes of the solutions described in parts (a) and (b) are mixed.