Combined Class Questions Ionic Equilibrium PDF

Physical Chemistry Combined Class Questions Ionic Equilibrium By- Sudhanshu Sir NOTE Don’t ask for the answers. All these questions are discussed in the class and their solutions are in the class notes pdf. QUESTION Conjugate base for Bronsted acids H2O and HF are A H3O+ an...

Physical Chemistry Combined Class Questions Ionic Equilibrium By- Sudhanshu Sir NOTE Don’t ask for the answers. All these questions are discussed in the class and their solutions are in the class notes pdf. QUESTION Conjugate base for Bronsted acids H2O and HF are A H3O+ and F–, respectively B OH– and F–, respectively C H3O+ and H2F+, respectively D OH– and H2F+, respectively QUESTION The conjugated acid of O–2 ion is- A O2+ B H+ C H3O+ D OH– QUESTION The conjugated base of (CH3)2 NH2+ is– A CH3NH2 B (CH3)2N+ C (CH3)2N D (CH3)2NH QUESTION In the reaction NH3 + H2O → NH4+ + OH– water behaves as– A Acid B Base C Neutral D Both acid and Base QUESTION In the reaction HNO3 + H2O → H3O+ + NO3– the conjugate base of HNO3 is– A H2O B H3O+ C NO3– D H3O+ and NO3– QUESTION Which of the following can act both as Bronsted acid and Bronsted Base? A Cl– B HSO4– C H3O+ D OH– QUESTION In the reaction, Adds proton NH3(aq) + H2O(l) ⇌ NH4+(aq) + OH– (aq) X Y Conjugate Conjugate acid base Lose proton X and Y respectively are A neutral and acid B acid and base C base and acid D base and neutral QUESTION Which equilibrium can be described as an acid-base reaction using the Lewis acid-base definition, but not using Bronsted-Lowry definition? A NH3 + CH3COOH ⇌ CH3COO¯ + NH4+ B H2O + CH3COOH ⇌ H3O+ + CH3COO– C 4NH3 + [Cu(H2O)4]2+ ⇌ [Cu(NH3)4]2+ + 4H2O D 2NH3 + H2SO4 ⇌ 2NH4+ + SO42– QUESTION Which of the following cannot act both as Bronsted acid and as Bronsted base? [NEET (Odhisa) 2019] A HCO3– B NH3 C HCl D HSO4– QUESTION Which of the following is least likely to behave as Lewis base? [CBSE AIPMT 2011] A OH– B H2O C NH3 D BF3 QUESTION Which one of the following is the weakest acid? A HCl B HF C H2SO4 D HNO3 QUESTION For which, dilution law is applicable? A NaCl B NaOH C CH3COONa D CH3COOH QUESTION 𝟐 If [H+] = × 10–4 then find pH? 𝟑 A 2.7 B 4.176 C 2 D 1 QUESTION If [OH–] = 5.0  10–5 M then pH will be A 5 – log 5 B 9 + log 5 C log 5 – 5 D log 5 – 9 QUESTION pOH of 0.002 M HNO3 is: A 11 + log 2 B 11 – log 2 C –3 + log 2 D None of these QUESTION The pH of 0.01 M NaOH (aq) solution will be A 7.01 B 2 C 12 D 9 QUESTION The hydroxide ion concentration of a wine is 8 × 10–11 M. What is the pH of the wine? A 2.10 B 2.9 C 3.9 D 4.9 QUESTION If pH = 3.31, then find out [H+] (Approx) A 3.39 × 10-4 B 5 × 10-4 C 3.0 × 10-3 D None QUESTION A beer has a pH of 4.30. What is the [H3O+]? A 3.0 × 10–4 B 2.0 × 10–4 C 2.0 × 10–3 D 5.0 × 10–5 QUESTION 2g of NaOH is dissolved in water to make 1L solution. The pH of solution is A 10.25 B 8.256 C 12.70 D 10.89 QUESTION For a 100 ml solution of 10–2 M NaOH the ratio pH : pOH would be- A 6:1 B 1:6 C 2:1 D 1010 : 1 QUESTION The number of H+ ions present in 1 mL of a solution having pH = 13 is: A 1013 B 6.023 × 1013 C 6.023 × 107 D 6.023 × 1010 QUESTION What is the pH of a 0.015 M Ba (OH)2 solution? A 1.82 B 1.52 C 12.48 D 12.18 QUESTION The pH of a solution is 6.0. In this solution- A [H+] = 100 [OH–] B [H+] = 10 [OH–] C [H+] = [OH–] D [H+] = [OH–] QUESTION At a 25oC temperature, pH of pure water is found to be 4. Determine pKw at the same temperature? QUESTION The unit of ionic product of water Kw are A Mol–1L–1 B Mol–2 L–2 C Mol–2 L–1 D Mol2 L–2 QUESTION At 90°C, pure water has [H3O+] = 10–6 mole litre–1. What is the value of Kw at 90°C? A 10–6 B 10–12 C 10–14 D 10–8 QUESTION The pKw of water at 50°C is 13.40. An aqueous solution at 50°C has pH = 7. This solution is– A Acidic B Alkaline C Neutral D Amphoteric QUESTION In the following reaction, H2O(l) + H2O(l) ֖ H3O+(aq) + OH–(aq) Acid X Conjugate acid Y X and Y respectively are A base and conjugate acid B acid and conjugate base C base and conjugate base D acid and conjugate acid QUESTION The pH of solution is increased from 3 to 6. Its H+ ion concentration will be: A Reduced to half B Doubled C Reduced by 1000 times D Increased by 1000 times QUESTION An aqueous solution of HCl is 10–9 M HCl. The pH of the solution should be: A 9 B Between 6 and 7 C 7 D Unpredictable QUESTION 0.001 N KOH solution has the pH: A 10–1 B 3 C 11 D 2 QUESTION The pH of a 10–10 M NaOH solution is nearest to: A 10 B 7 C 4 D –10 QUESTION What is the quantity of NaOH present in 250 cc of the solution, so that it gives a pH = 13? A 10–13 g B 10–1 g C 1.0 g D 4.0 g QUESTION 10–6 M HCI is diluted to 100 times. Its pH is A 6.0 B 8.0 C 6.95 D 9.5 QUESTION The pH of a solution is 2. Its pH is to be changed to 4. Then the H+ concentration of original solution has to be: A Halved B Doubled C Increased by 100 times D Decreased by 100 times QUESTION How many litres of water must be added to 1L of an aqueous solution with a pH of 1 to create an aqueous solution of pH of 2? A 49 L B 9L C 79 L D 59 L QUESTION The pH of solutions A, B, C and D are 9.5, 2.5, 3.5 and 5.5 respectively. The most acidic solution is- A D B C C A D B QUESTION If pure water has pkw = 13.36 at 50°C, the pH of pure water will be- A 6.68 B 7.0 C 7.13 D 6.0 QUESTION Degree of ionisation of water at 25°C is: A 1.8  10-9% B 1.8  10-7% C 1.8  10-3% D 1.8  10-12% QUESTION Which of the following on ionization would give concentration of anion equal to 3C? A AB B AB2 C AB3 D A 2B QUESTION A solution has pOH equal to 13 at 298 K. The solution will be: A highly acidic B highly basic C moderately basic D unpredictable QUESTION Equal volumes of three acid solutions of pH 3, 4 and 5 are mixed in a vessel. What will be the H+ ion concentration in the mixture? A 1.11 × 10–4 M B 3.7 × 10–4 M C 3.7 × 10–3 M D 1.11 × 10–3 M QUESTION If 100 mL of pH = 3 and 400 mL of pH = 3 is mixed, what will be the pH of the mixture A 3.2 B 3.0 C 3.5 D 2.8 QUESTION The pH of the solution produced when an aqueous solution of strong acid pH 5 is mixed with equal volume of an aqueous solution of strong acid of pH 3 is: A 3.3 B 3.5 C 4.5 D 4.0 QUESTION The pH of the solution containing 10 mL of a 0.1M NaOH and 10 mL of 0.05M H2SO4 would be A Zero B 1 C >7 D 7 QUESTION The pH of a 0.02 M ammonia solution which is 5% ionised will be: A 2 B 11 C 5 D 7 QUESTION 8 g NaOH and 4.9 g H2SO4 are present in one litre of the solution. What is its pH? A 1 B 13 C 12 D 2 QUESTION 4.0 g of NaOH and 4.9 g of H2SO4 are dissolved in water and volume is made upto 250 ml. The pH of this solution is– A 7.0 B 1.0 C 2.0 D 12.0 QUESTION What is the pH of the resulting solution when equal volumes of 0.1 M NaOH and 0.01 M HCl are mixed? A 7.0 B 1.04 C 12.65 D 2.0 QUESTION The pH of the solution obtained by mixing 10 mL of 0.1 M HCl and 10 mL of 0.1 M NaOH is: A 8 B 2 C 7 D None of these QUESTION Following four solutions are prepared by mixing different volumes of NaOH and HCl of different concentrations, pH of which one of them will be equal to 2? M M A 100 mL HCl + 100 mL NaOH 10 10 M M B 75 mL HCl + 25 mL NaOH 10 10 M M C 60 mL HCl + 40 mL NaOH 10 10 D 55 mL M HCl + 45 mL M NaOH 10 10 QUESTION Calculate the pH of solution formed by mixing of 𝟑𝟎𝟎𝐦𝐥 of 𝟎. 𝟐 𝐌 𝐍𝐚𝐎𝐇, 𝟐𝟎𝟎 𝐦𝐥 of 𝟎. 𝟒𝐌𝐇𝟐𝐒𝐎𝟒 & 500 mL of 𝟎. 𝟏 𝐌𝐂𝐚(𝐎𝐇)𝟐. QUESTION The pH of a mixture when a 50 mL solution of pH = 1 is mixed with a 50 mL of pH = 2 is A 0.56 B 1.26 C 1.76 D 2.06 QUESTION Which of the following is the weakest acid? A Phenol (Ka = 1.3  10-10) B Hydrocyanic acid (Ka = 4.9  10-10) C Acetic acid (Ka = 1.8  10-5) D Benzoic acid (Ka = 6.5  10-5) QUESTION Which of the following is the strongest base? A C6H5NH2 (pKb = 9.42) B C6H5NHCH3 (pKb = 9.15) C C6H5N(CH3)2 (pKb = 8.94) D C6H5NHC2H5 (pKb = 8.89) QUESTION Find out the value of a of 10-2 M HCN solution if [H+] = 10-3. QUESTION For 10 M CH3COOH solution if Ka = 10-5 then find out: (i) α (ii) [H+] (iii) pH QUESTION A 0.2 molar solution of formic acid is 3.2% ionised. Its ionisation constant is A 9.6  10-3 B 2.1  10-4 C 1.25  10-6 D 4.8  10-5 QUESTION Calculate the sum of [H+] & [OH–] present in pure water at 25oC. QUESTION The pH of 0.10 M acetic acid having Ka = 1.8  10-5 is A 2.9 B 5.6 C 6.8 D 3.4 QUESTION A 0.01 M ammonia solution is 5% ionised. The concentration of OH ion is A 0.005 M B 0.0001 M C 0.0005 M D 0.05 M QUESTION What is H+ ion concentration of 5  10-3 M H2CO3 solution having a 10% dissociation A 10–3 B 10–2 C 10–1 D 5  10–2 QUESTION If Ka of HCN = 4 × 10–10, then the pH of 2.5 × 10–1 molar HCN (aq) is- A 4.2 B 4.7 C 0.47 D 5.0 QUESTION A 0.01 M ammonia solution is 5% ionized. The concentration of OH– ion is A 0.005 M B 0.0001 M C 0.0005 M D 0.05 M QUESTION The molarity of nitrous acid at which its pH becomes 2. (Ka = 4.5 × 10–4)- A 0.3333 B 0.4444 C 0.6666 D 0.2222 QUESTION The ionisation constant of 𝐇𝐅 is 𝟑. 𝟐 × 𝟏𝟎−𝟒. Calculate its 𝜶 in its 𝟎. 𝟎𝟐𝐌 soln. Calculate its 𝐩𝐇 and conc" of all species present in solution. QUESTION The pH of 𝟎. 𝟏𝐌 monobasic acid is 4.5. Calculate the concentration of 𝐇+ at 𝐞𝐪𝐦. Also Calculate 𝐊 𝐚 & pKa. QUESTION The pH of a 0.1 M aqueous solution of a weak acid (HA) is 3. What is its degree of dissociation? A 1% B 10% C 50% D 25% QUESTION 0.01 M acetic acid solution is 1% ionised, then pH of this acetic acid solution is: A 3 B 2 C 4 D 1 QUESTION Find out the value of  of 10–2 M NH4OH solution if [OH–] = 10–3. A 0.1% B 10% C 1% D 5% QUESTION For 10–3 M CH3COOH solution if Ka = 10–5 then pH is: A 12 B 14 C 4 D 1 QUESTION For 10–3 M H3PO3 if  = 10% then find out the value of pH? A 3.7 B 4.7 C 5 D 2 QUESTION What would be [H+] of 0.006 M benzoic acid (Ka = 6 × 10–5) A 0.6 × 10–4 B 6 × 10–4 C 6 × 10–3 D 3.6 × 10–4 QUESTION Find out Ka for 10–2 M HCN acid, having pOH 10: A Ka = 10–4 B Ka = 10–2 C Ka = 10–5 D Ka = 10–6 QUESTION Ka for HF is 3.5 × 10–4. Calculate Kb tor the fluoride ion. A 3.5  10–4 B 1.0  10–7 C 2.9  10–11 D 1.0  10–14 QUESTION The Ka for a weak acid HX is 10-6, then the ionisation constant of X- will be: A 10-6 B 10-8 C 10-14 D 10-4 QUESTION The pKb for fluoride ion at 25°C is 10.83, the ionisation constant of hydrofluoric acid at this temperature is A 2.72  10-5 B 3.52  10-3 C 6.76  10-4 D 5.38  10-2 QUESTION Calculate the pKb of 𝟎. 𝟎𝟎𝟒𝐌 𝐇𝐲𝐝𝐫𝐚𝐳𝐢𝐧𝐞 if pH of the solution is 𝟗. 𝟕. Also calculate 𝐊𝐚 of 𝐍𝐇𝟐 − 𝐍𝐇𝟑 . QUESTION Determine the ionization constant of CH3COOH if Kb for CH3COO– at 25oC is 5  10–10. QUESTION At infinite dilution, the percentage ionisation for both strong and weak electrolytes is A 1% B 20% C 50% D 100% QUESTION The dissociation constant of acetic acid at a given temperature is 1.69  10–5. The degree of dissociation of 0.01 M acetic acid in the presence of 0.01 M HCl is equal to A 0.41  10–2 B 0.18  10–7 C 0.169  10–2 D 0.013  10–4 QUESTION Assertion : NaCl + HCl does not experience common ion effect. Reason : Both NaCl and HCl are strong electrolytes. A Both A and R are correct and R is the correct explanation of A. B Both A and R are correct, but R is not the correct explanation of A. C A is correct but, R is incorrect. D R is correct but, A is incorrect. QUESTION pH of a strong diprotic acid (H2A) at concentrations: (i) 10–4 M (ii) 10–4 N are respectively: A 3.7 and 4.0 B 4 and 3.7 C 4 and 4 D 3.7 and 3.7 QUESTION Buffer solutions can be prepared from mixtures of A HCl and NaCl B NaH2 PO4 and Na2 HPO4 C CH3 COOH + NaCl D NH4 OH + NH3 QUESTION Which one of the following pairs of solution is not an acidic buffer? A H2CO3 and Na2CO3 B H2PO4 and Na3PO4 C HClO4 and NaClO4 D CH3COOH and CH3COONa QUESTION On diluting a buffer solution, its pH: A Increases B Decreases C Remains same D Can't say QUESTION Which of the following combinations of CH3COOH + NaOH would result in the formation of acidic buffer? A 1 : 1 mol ratio B 2 : 1 mol ratio C 1 : 2 mol ratio D Both (A) and (C) QUESTION Which will make basic buffer? A 100 mL of 0.1 M CH3COOH + 100 mL of 0.1 M NaOH B 100 mL of 0.1 M HCl + 200 mL of 0.1 M NH4OH C 100 mL of 0.1 M HCl + 100 mL of 0.1 M NaOH D 50 mL of 0.1 M NaOH + 25 mL of 0.1 M CH3COOH QUESTION When 2 moles of HCl is added to 1 L. of an acidic buffer solution, its pH changes from 3.9 to 3.4. Find its buffer capacity. QUESTION The pH of a buffer solution will be equal to the pKa of acid, only if A Molar concentration of acid is greater than molar concentration of conjugate base. B Molar concentration of acid is smaller than molar concentration of conjugate base. C Molar concentration of acid is equal to the molar concentration of conjugate base. D Molar concentration of acid is almost negligible. QUESTION A buffer solution is one which has– A reserved acid B reserved base C almost constant pH D pH equal to 7 QUESTION The pH of blood circulating in a human body is maintained around 7.4 by the action of the buffer system: A CH3COOH/CH3COONa B NH4Cl/NH3 C H2PO42– D H2CO3/HCO3– QUESTION What is [H+] in mol/L of a solution that is 0.20 M in CH3COONa and 0.1 M in CH3COOH? Ka for CH3COOH is 1.8 × 10–5? A 3.5 × 10–4 B 1.1 × 10–5 C 1.8 × 10–5 D 9.0 × 10–6 QUESTION For preparing a buffer solution of pH 6 by mixing sodium acetate and acetic acid, the ratio of the concentration of salt and acid should be (Ka = 10–5) A 1 : 10 B 10 : 1 C 100 : 1 D 1 : 100 QUESTION Components of buffer solution are 0.1M HCN (pka = 9.30) and 0.2 M NaCN. What is the pH of the solution A 9.61 B 6.15 C 2.0 D 4.2 QUESTION pH of a solution of 10 ml, 1N sodium acetate and 50 ml, 2N acetic acid (Ka = 1.8 × 10–5), is approximately A 4 B 5 C 6 D 7 QUESTION The pH of the solution containing 50mL, each of 0.10 M sodium acetate and 0.01 M acetic acid is [Given pKa of Ca3COOH = 4.57] A 2.57 B 5.57 C 3.57 D 4.57 QUESTION Solution of 0.1 M NH4OH and 0.1 M NH4Cl has pH 9.25, Then find out pKb of NH4OH A 9.25 B 4.75 C 3.75 D 8.25 QUESTION A certain buffer solution contains equal concentration of X– and HX. The Kb for X– is 1 × 10–10. The pH of the buffer is– A 4 B 7 C 10 D 14 QUESTION In a mixture of a weak acid and its salt, the ratio of concentration of acid to salt is increased ten-fold. The pH of the solution A Decreases by one B Increases by one-tenth C Increases by one D Increases ten-fold QUESTION The pKa of a weak acid (HA) is 4.5. The pOH of an aqueous buffered solution of HA in which 50% of the acid is ionized is A 4.5 B 2.5 C 9.5 D 7.0 QUESTION If 40 ml of 0.2 M KOH is added to 160 ml of 0.1 M HCOOH [Ka = 2 × 10–4], the pOH of the resulting solution is A 3.4 B 3.7 C 7 D 10.3 QUESTION To 1.0 L solution containing 0.1 mol each of NH3 and NH4Cl, 0.05 mol HCl is added. The change in pOH will be (pKa for NH3 = 4.74) A 0.30 B –0.30 C 0.48 D –0.48 QUESTION 100 mL of a buffer solution contains 0.1M each of weak acid HA and salt NaA. How many gram of NaOH should be added to the buffer so that its pH will be 6? (Ka of HA = 10–5) A 0.328 B 0.458 C 4.19 D None QUESTION Which salt is not an example of acidic salt: A HCOONa B NaH2PO2 C NaHS D (A) And (B) Both QUESTION An aqueous solution of sodium carbonate is alkaline because sodium carbonate is a salt of A Weak acid and weak base B Strong acid and weak base C Weak acid and strong base D Strong acid and strong base QUESTION Which of the following cannot be hydrolysed A A salt of weak acid and strong base B A salt of strong acid and weak base C A salt of weak acid and weak base D A salt of strong acid and strong base QUESTION Assertion : An aqueous solution of NH4NO3 is acidic in characters. Reason : NH4NO3 in an aqueous solution undergoes anionic hydrolysis. A Both A and R are correct and R is the correct explanation of A. B Both A and R are correct, but R is not the correct explanation of A. C A is correct but, R is incorrect. D R is correct but, A is incorrect. QUESTION Calculate pH of 10–2 M KCN solution if dissociation constant of HCN = 10–10. QUESTION Calculate the degree of hydrolysis of a mixture containing 0.1N NH4OH and 0.1 N HCN If Ka = 10–5 and Kb = 10–5 QUESTION What is the pH of 1 M CH3COONa solution? Ka of acetic acid = 1.8  10–5, Kw = 10–14 mol2 L–2 A 2.4 B 3.6 C 4.8 D 9.4 QUESTION Calculate the pH of aqueous solution of 1.0 M HCOONH4 assuming complete dissociation (pKa of HCOOH = 3.8 and pKb of NH3 = 4.8) A 3.5 B 4.5 C 5.5 D 6.5 QUESTION pKa of a weak acid (HA) and pKb of a weak base (BOH) are 3.2 and 3.4, respectively. The pH of their salt (AB) solution is: A 6.9 B 7.0 C 1.0 D 7.2 QUESTION pH of 0.1 M NaCN solution is 11, then the percentage hydrolysis is– A 0.1% B 1% C 0.01% D 10% QUESTION HX is a weak acid (Ka = 10–5). It forms a salt NaX (0.1 M) on reacting with caustic soda. The degree of hydrolysis of NaX is A 0.01% B 0.0001% C 0.1% D 0.5% QUESTION The pKb of dimethylamine and pKa of acetic acid are 3.27 and 4.77 respectively at T(K). The correct option for the pH of dimethylammonium acetate solution is: A 7.75 B 6.25 C 8.50 D None of these QUESTION Which is the correct alternate for hydrolysis constant of NH4CN Kw A Ka Kw B K a  Kb Kb C c Ka D Kb QUESTION The pH of 0.1 M NH4Cl solution is 5.13. What will be the dissociation constant of NH4OH A 1.8 × 10–7 B 1.8 × 10–9 C 1.8 × 10–5 D None QUESTION If a salt of strong acid and weak base hydrolyses appreciably ( = 0.1), which of the following formula is to be used to calculate degree of hydrolysis ‘’? Kw A α= Ka ⋅ a Kw B α= Kb ⋅ K Kw C α= K b ⋅ Kb D None of these QUESTION What is the hydrolysis constant of the OCl– ion? The ionization constant of HOCl is 3.0 × 10–8. A 3.33 × 10–8 B 3.33 × 10–7 C 3.0 × 10–7 D 3.33 × 10–6 QUESTION Let the solubility of an aqueous solution of Mg(OH)2 be x then its Ksp is A 4x3 B 108x5 C 27x4 D 9x QUESTION A salt M2X3 dissolves in water such that its solubility is x mole/litre. Its Ksp is: A x5 B 6x2 C 108 x5 D 6x5 QUESTION The Ksp for Cr(OH)3 is 1.6  10–3. The molar solubility of this compound in water is A 2 1.6 × 10−30 4 B 1.6 × 10−30 4 1.6 × 10−30 C 27 1.6 × 10−30 D 27 QUESTION Which is the correct representation of the solubility product constant of Ag2CrO4 A [Ag+]2 [CrO4–2] B [Ag+] [CrO4–2] C [2Ag+] [CrO4–2] D [2Ag+]2 [CrO4–2] QUESTION The solubility in water of a sparingly soluble salt AB2 is 1.0 × 10–5 mol L–1. Its solubility product will be A 4 × 10–15 B 4 × 10–10 C 1 × 10–15 D 1 × 10–10 QUESTION The solubility product of a salt having general formula MX2, in water is 4 × 10–12. The concentration of M2+ ions in the aqueous solution of the salt is A 2.0 × 10–6 M B 1.0 × 10–4 M C 1.6 × 10–4 M D 4.0 × 10–10 M QUESTION Zirconium phosphate [Zr3(PO4)4] dissociates into three zirconium cations of charge +4 and four phosphate anions of charge –3. If molar solubility of zirconium phosphate is denoted by S and its solubility product by Ksp then which of the following relationship between S and Ksp is correct? A S = {Ksp/(6912)1/7} B S = (Ksp/6912)1/7 C S = {Ksp/1441/7} D S = {Ksp/(6912)7} QUESTION The necessary condition for saturated solution is: A Product of ionic concentrations = Solubility product B Product of ionic concentrations < solubility product C Product of ionic concentrations > solubility product D None of the above QUESTION A precipitate of AgCl is formed when equal volumes of the following are mixed. [Ksp for AgCl = 10–10] A 10–4 M AgNO3 and 10–7 M HCl B 10–5 M AgNO3 and 10–7 M HCl C 10–5 M AgNO3 and 10–4 M HCl D 10–6 M AgNO3 and 10–6 M HCl QUESTION When equal volumes of the following solutions are mixed, precipitation of AgCl (Ksp = 1.8 × 10–10) will occur only with A 10–4 M(Ag+) and 10–4 M (Cl–) B 10–5 M (Ag+) and 10–5 M (Cl–) C 10–6 M (Ag+) and 10–6 M (Cl–) D 10–10 M (Ag+) and 10–10 M (Cl–) QUESTION At 25°C, the solubility product of Mg (OH)2 is 1.0 × 10–11. At which pH, will Mg2+ ions start precipitating in the form of Mg (OH)2 from a solution of 0.001 M Mg2+ ions? A 9 B 10 C 11 D 8 QUESTION When 15mL of 0.05 M AgNO3 is mixed with 45.0 mL of 0.03 M K2CrO4, predict whether precipitation of Ag2CrO4 occurs or not? Ksp of Ag2CrO4 = 1.9  10–12. QUESTION The solubility product of different sparingly soluble salts are 1. XY = 4 × 10–2 2. X2Y = 3.2 × 10–11 3. XY3 = 2.7 × 10–31 The increasing order of solubility is A 1, 3, 2 B 2, 1, 3 C 1, 2, 3 D 3, 1, 2 QUESTION Calculate the simultaneous solutions of AB and AC when as (Ksp)AB = 10–12 and (Ksp)AC = 5  10–13. QUESTION Calculate the [F–] in a solution saturated with respect to MgF2 and SrF2. Ksp(MgF2) = 6.0  10–9; Ksp(SrF2) = 3.0  10–9. QUESTION CaCO3 and BaCO3 have solubility product values 1  10–8 and 5  10–9, respectively. If water is shaken up with both solids till equilibrium is reached, the concentration of CO32– ion is A 1.5  10–8 B 1.225  10–4 C 2.25  10–9 D None of these QUESTION The ionization constant of dimethylamine is 5.4 × 10–4. Calculate its degree of ionization in its 0.02M solution. What percentage of dimethylamine is ionized if the solution is also 0.1M in NaOH? QUESTION The ionization constant of phenol is 1.0 × 10–10. What is the concentration of phenolate ion in 0.05 M solution of phenol? What will be its degree of ionization if the solution is also 0.01M in sodium phenolate? QUESTION Calculate the pH of a 0.10M ammonia solution. Calculate the pH after 50.0 mL of this solution is treated with 25.0 mL of 0.10M HCl. The dissociation constant of ammonia, Kb = 1.77 × 10–5. QUESTION What is the pH of a buffer solution which is 0.250 M in benzoic acid, C6H5COOH, and 0.150 M in sodium benzoate, C6H5COONa, if Ka for benaoic acid is 6.5  10–5? A 3.40 B 3.97 C 4.19 D 4.41 QUESTION If 20 mL of 0.1 M NaOH is added to 30 mL of 0.2 M CH3COOH (pKa = 4.74), the pOH of the resulting solution is: A 4.44 B 9.56 C 8.96 D 9.26 QUESTION A 0.02M solution of pyridinium hydrochloride has pH = 3.44. Calculate the ionization constant of pyridine QUESTION The solubility product constant of Ag2CrO4 and AgBr are 1.1 × 10–12 and 5.0 × 10–13 respectively. Calculate the ratio of the molarities of their saturated solutions QUESTION The ionization constant of nitrous acid is 4.5 × 10–4. Calculate the pH of 0.04 M sodium nitrite solution and also its degree of hydrolysis QUESTION The pH of 0.1M solution of cyanic acid (HCNO) is 2.34. Calculate the ionization constant of the acid and its degree of ionization in the solution QUESTION Find out pH of solution having 2  10–3 moles of OH– ion's in 2 litre solution: A pH = 3 B pH = 3 +log2 C pH = 3 –log2 D pH = 11 QUESTION A metal hydroxide of molecular formula M(OH)4 is 50% ionised. Its 0.0025M solution will have the pH: A 12 B 2 C 4 D 11.7 QUESTION If a is the degree of dissociation of weak dibasic organic acid and y is the hydrogen ion concentration, what is the initial concentration of acid: a y −1 A M 2 B y(a)–1M y a −1 C M 2 D None of them QUESTION The degree of dissociation of acetic acid is given by the expression a = 0.1  C–1 (where C = concentration of the acid) What is the pH of the solution: A 1 B 2 C 3 D 4 QUESTION Find out Ka for 10–2 M HCN acid, having pOH is 10: A Ka = 10–4 B K = 10–2 a C Ka = 10–5 D None of them QUESTION The extent of ionisation increases (weak electrolytes) A With the increase in concentration of solute B On decreasing the temp. of solution C On addition of excess of water to the solution D On stirring the solution vigorously QUESTION Correct statement for HCN weak acid at 25°C temperature: Ka A a= + H K a OH− B a= Kw C (A) & (B) both D Kb = Ca2 QUESTION At 373 K, temp. the pH of pure H2O can be: A 7 C =7 D =0 QUESTION Which of the following is an acid salt: A Na2S B Na2SO3 C NaHSO3 D Na₂SO₄ QUESTION What will be the pH of 1.0 M ammonium formate solution, If Ka = 1 × 10–4 acid Kb = 1  10–5: A 6.5 B 7.5 C 8.0 D 9.0 QUESTION Which salt will not undergo hydrolysis: A KCI B Na2SO4 C NaCl D All QUESTION For anionic hydrolysis, pH is given by: 1 1 1 A pH = pK w − pK b − logc 2 2 2 1 1 1 B pH = pK w + pK a − pKb 2 2 2 1 1 1 C pH = pK w + pK a + logc 2 2 2 D None of above QUESTION If pKb for CN at 25°C is 4.7. The pH of 0.5M aqueous NaCN solution is: A 12 B 10 C 11.5 D 11 QUESTION In solubility of salts M2X, QY2 and PZ2 equal, then the relation between their Ksp will be: A Ksp(M2X) > Ksp(QY2) > Ksp(PZ2) B Ksp(M2X) = Ksp(QY2) < Ksp(PZ2) C Ksp(M2X) > Ksp(QY2) = Ksp(PZ2) D Ksp(M2X) = Ksp(QY2) = Ksp(PZ2) QUESTION Concentration of Ag+ ions in saturated solution of Ag2CrO4 at 20°C is 1.5  10–4 mol L–1 At 20oC the solubility product of Ag2CrO4 is: A 3.375  10–12 B 1.6875  10–10 C 1.68  10–12 D 1.6875  10–11 QUESTION If the solubility of AgCl (formula mass = 143) in water at 25°C is 1.43  10–4 g/100 mL of solution then the value of Ksp will be: A 1  10–5 B 2  10–5 C 1  10–10 D 2  10–10 QUESTION If the salts M2X, QY2 and PZ3 have the same solubilities, their Ksp values are related as - (S < 1) A Ksp(M2X) = Ksp(QY2) < Ksp(PZ3) B Ksp (M2X) > Ksp(QY2) = Ksp(PZ3) C Ksp(M2X) = K (QY2) > Ksp (PZ3) D Ksp(M2X) > Ksp(QY2) > Ksp(PZ3) QUESTION The pH of solution is increased from 3 to 6. Its H+ ion concentration will be: A Reduced to half B Doubled C Reduced by 1000 times D Increased by 1000 times QUESTION The pOH of beer is 10.0. The hydrogen ion concentration will be: 𝐊𝐰 (1) 10–10 (2) −𝟏𝟎 𝟏𝟎 𝐊𝐰 (3) (4) 10–4 𝟏𝟎−𝟖 A 1, 4 B 2, 4 C 1, 2, 3 D None QUESTION An aqueous solution whose pH = 0 is: A Basic B Acidic C Neutral D Amphoteric QUESTION Following five solution of KOH were prepare as- First → 0.1 moles in 1 L Second → 0.2 moles in 2 L Third → 0.3 moles in 3 L Fourth → 0.4 moles in 4 L Fifth → 0.5 moles in 5 L The pH of resultant solution is: A 2 B 1 C 13 D 7 QUESTION 𝐍 For H2SO4, pH value is: 𝟏𝟎 A 1 B 0.586 C 0.856 D None QUESTION H2X is a dibasic acid which dissociates completely in water. Which one of the following is the molarity of an aqueous solution of this acid which has a pH of 1: A 0.1 B 0.05 C 0.2 D 0.5 QUESTION When 1.0 mL of dil.HCl acid is added to 100 mL of a buffer solution of pH 4.0. The pH of the solution: A Becomes 7 B Does not change C Becomes 2 D Becomes 10 QUESTION Which of the following solutions does not act as buffer: A H₃PO₄ + NaH2PO4 B NaHCO3 + H₂CO₃ C NH4Cl + HCI D CH3COOH + CH3COONa QUESTION On addition of NaOH to CH3COOH solution, 60% of the acid is neutralised. If pKa of CH3COOH is 4.7 then the pH of the resulting solution is: A More than 4.7 but less than 5.0 B Less than 4.7 but more than 4.0 C More than 5.0 D Remains unchanged QUESTION Half of the formic acid solution is neutralised on addition of a KOH solution to it. If Ka(HCOOH) = 2 × 10–4 then pH of the solution a is: (log 2 = 0.3010) A 3.6990 B 10.3010 C 3.85 D 4.3010 QUESTION When 0.02 moles of NaOH are added to a litre of buffer solution, its pH changes from 5.75 to 5.80. What is its buffer capacity: A 0.4 B 0.05 C –0.05 D 2.5 QUESTION Calculate the pH of a buffer prepared by mixing 300 cc of 0.3 M NH3 and 500 cc of 0.5 M NH4Cl. Kb for NH3 = 1.8  10–5: A 8.1187 B 9.8117 C 8.8117 D None of these QUESTION What amount of sodium propanoate should be added to one litre of an aqueous solution containing 0.02 mole of propanoic acid (Ka = 1.34  10–5 at 25oC) to obtain a buffer solution of pH 4.75: A 4.52  10–2 M B 3.52 10–2 M C 2.52  10–2 M D 1.52  10–2 M QUESTION What will be the pH of the solution, if 0.01 moles of HCl is dissolved in a buffer solution containing 0.02 moles of propanoic acid (Ka = 1.34  10–5) and 0.0152 moles of salt, at 25oC: [log(0.173) = –0.76] A 3.11 B 4.11 C 5.11 D 6.11