N Awasthi Physical Chemistry
A buffer solution 0.04 M in Na2HPO4 and 0.02 in Na3PO4 is prepared. The electrolytic oxidation of 1.0 milli-mole of the organic compound RNHOH is carried out in 100 mL of the buffer. The reaction is RNHOH + H2O→RNO2+4H^+ +4e− The approximate pH of solution after the oxidation is complete is : [Given:forH3PO4,pKa1=2.2,pKa2=7.20,pKa3=12]
22
Nov
A buffer solution 0.04 M in Na2HPO4 and 0.02 in Na3PO4 is prepared. The electrolytic oxidation of 1.0 milli-mole of the organic compound RNHOH is carried out in 100 mL of the buffer. The reaction is RNHOH + H2O→RNO2+4H^+ +4e− The approximate pH of solution after the oxidation is complete is : [Given:forH3PO4,pKa1=2.2,pKa2=7.20,pKa3=12] 1.0 L [...]
Which of the following expression for % dissociation of a monoacidic base (BOH) in aqueous solution at appreciable concentration is not correct?
22
Nov
Which of the following expression for % dissociation of a monoacidic base (BOH) in aqueous solution at appreciable concentration is not correct? Which of the following expression for % dissociation of a monoacidic base (BOH) in aqueous solution at appreciable concentration is not correct? November 22, 2020 Category: Chapter 6 - Ionic Equilibrium (Level 1 [...]
A 1.025 g sample containing a weak acid HX (mol. Mass=82) is dissolved in 60 mL. water and titrated with 0.25 M NaOH. When half of the acid was neutralised the pH was found to be 5.0 and at the equivalence point the pH is 9.0. Calculate mass percentage of HX in sample :
22
Nov
A 1.025 g sample containing a weak acid HX (mol. Mass=82) is dissolved in 60 mL. water and titrated with 0.25 M NaOH. When half of the acid was neutralised the pH was found to be 5.0 and at the equivalence point the pH is 9.0. Calculate mass percentage of HX in sample : 1.0 [...]
How many gm of solid KOH must be added to 100 mL of a buffer solution to make the pH of solution 6.0, if it is 0.1 M each w.r.t. acid HA and salt K A. [Given : pKa (HA)=5]
22
Nov
How many gm of solid KOH must be added to 100 mL of a buffer solution to make the pH of solution 6.0, if it is 0.1 M each w.r.t. acid HA and salt K A. [Given : pKa (HA)=5] How many gm of solid KOH must be added to 100 mL of a buffer [...]
How many gm of solid KOH must be added to 100 mL of a buffer solution to make the pH of solution 6.0, if it is 0.1 M each w.r.t. acid HA and salt K A. [Given : pKa (HA)=5]
22
Nov
How many gm of solid KOH must be added to 100 mL of a buffer solution to make the pH of solution 6.0, if it is 0.1 M each w.r.t. acid HA and salt K A. [Given : pKa (HA)=5] How many gm of solid KOH must be added to 100 mL of a buffer [...]
Fe(OH)2 is diacidic base has Kb1=10^−4 and Kb2 = 2.5 × 10^−6 What is the concentration of Fe(OH)2 in 0.1 M Fe(NO3)2 solution?
22
Nov
Fe(OH)2 is diacidic base has Kb1=10^−4 and Kb2 = 2.5 × 10^−6 What is the concentration of Fe(OH)2 in 0.1 M Fe(NO3)2 solution? Fe(OH)2 is diacidic base has Kb1=10^−4 and Kb2 = 2.5 × 10^−6 What is the concentration of Fe(OH)2 in 0.1 M Fe(NO3)2 solution? November 22, 2020 Category: Chapter 6 - Ionic Equilibrium [...]
Ka for the reaction; Fe^3 + (aq.)+H2O(l) ⇌ Fe(OH)^2 + (aq.)+H3O^+ (aq.) is 6.5×10^−3 . What is the maximum pH value which could be used do that at least 80% of the total ion (III) in a dilute solution exists as Fe^3+ ?
22
Nov
Ka for the reaction; Fe^3 + (aq.)+H2O(l) ⇌ Fe(OH)^2 + (aq.)+H3O^+ (aq.) is 6.5×10^−3 . What is the maximum pH value which could be used do that at least 80% of the total ion (III) in a dilute solution exists as Fe^3+ ? 1.0 L solution is prepared by mixing 61 g benzoic acid (pKa=4.2) [...]
1.0 L solution is prepared by mixing 61 g benzoic acid (pKa=4.2) with 72 g of sodium benzoate and then 300 mL 1.0 M HBr solution was added. The pH of final solution is :
22
Nov
1.0 L solution is prepared by mixing 61 g benzoic acid (pKa=4.2) with 72 g of sodium benzoate and then 300 mL 1.0 M HBr solution was added. The pH of final solution is : 1.0 L solution is prepared by mixing 61 g benzoic acid (pKa=4.2) with 72 g of sodium benzoate and then [...]
Amongst the following, the total number of compounds whose aqueous solution turns red litmus paper blue is: NaCN KCL CH3CooNH4 NaH2PO4 ZnCL2
18
Nov
Amongst the following, the total number of compounds whose aqueous solution turns red litmus paper blue is: NaCN KCL CH3CooNH4 NaH2PO4 ZnCL2 Amongst the following the total number of compounds whose aqueous solution turns red litmus paper blue is: NaCN KCL CH3CooNH4 NaH2PO4 ZnCL2 November 18, 2020 Category: Chapter 6 - Ionic Equilibrium (Level 1 [...]
10 mL of H2A(weak diprotic acid) solution is titrated against 0.1M NaOH. pH of the solution is plotted against volume of strong base added and following observation is made. If pH of the solution at first equivalence point is pH1 and at second equivalence point is pH2.Calculate the value of (pH_(2)-pH_(1))at25^ degree C Given: for H_(2)A,pK_(a_1)=4.6 and pK_(a_2)` =8, log 25=1.4
18
Nov
10 mL of H2A(weak diprotic acid) solution is titrated against 0.1M NaOH. pH of the solution is plotted against volume of strong base added and following observation is made. If pH of the solution at first equivalence point is pH1 and at second equivalence point is pH2.Calculate the value of (pH_(2)-pH_(1))at25^ degree C Given: for [...]