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Chemistry · EQUILIBRIUM
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Chemistry · EQUILIBRIUM
For a 0.10 M aqueous solution of a diprotic acid \( \text{H}_2\text{X} \), the ionization constants are \( K_{a_1} = 4.0 \times 10^{-5} \) and \( K_{a_2} = 1.6 \times 10^{-11} \). The concentration of divalent anion \( [\text{X}^{2-}] \) at equilibrium is:
Read answer →Chemistry · EQUILIBRIUM
When \( \text{HCl} \) gas is passed through a saturated solution of \( \text{NaCl} \), pure \( \text{NaCl} \) precipitates out while impurities like \( \text{MgSO}_4 \) and \( \text{Na}_2\text{SO}_4 \) remain dissolved. The underlying reason for this phenomenon is:
Read answer →Chemistry · EQUILIBRIUM
In the equilibrium \( \text{Fe}^{3+}(\text{aq}) + \text{SCN}^-(\text{aq}) \rightleftharpoons [\text{Fe}(\text{SCN})]^{2+}(\text{aq}) \) (deep red), what happens to the red colour intensity upon the addition of oxalic acid \( (\text{H}_2\text{C}_2\text{O}_4) \) and why?
Read answer →Chemistry · EQUILIBRIUM
The solubility of a salt \( \text{MX} \) of a weak monobasic acid \( \text{HX} \) depends on pH according to the relation \( S = \sqrt{K_{sp}(1 + \frac{[\text{H}^+]}{K_a})} \). If \( K_{sp} = 4.0 \times 10^{-10} \) and \( K_a = 1.0 \times 10^{-5} \), what is the molar solubility of \( \text{MX} \) at \( \text{pH} = 3.0 \)?
Read answer →Chemistry · EQUILIBRIUM
For the equilibrium \( \text{H}_2(\text{g}) + \text{I}_2(\text{g}) \rightleftharpoons 2\text{HI}(\text{g}) \), the value of \( K_c \) is \( 49.0 \) at a certain temperature. If \( 1.0\text{ mol} \) of \( \text{H}_2 \) and \( 1.0\text{ mol} \) of \( \text{I}_2 \) are placed in a \( 2.0\text{ L} \) flask and allowed to reach equilibrium, what is the total number of moles of \( \text{HI} \) present at equilibrium?
Read answer →Chemistry · EQUILIBRIUM
What is the \( [\text{H}^+] \) concentration in a solution containing \( 0.05\text{ M} \) acetic acid and \( 0.05\text{ M} \) sodium acetate? (Given: \( K_a \text{ of } \text{CH}_3\text{COOH} = 1.8 \times 10^{-5} \))
Read answer →Chemistry · EQUILIBRIUM
The molar solubility of zirconium phosphate, \( \text{Zr}_3(\text{PO}_4)_4 \), in pure water is \( S\text{ mol L}^{-1} \). The solubility product constant \( K_{sp} \) in terms of \( S \) is:
Read answer →Chemistry · EQUILIBRIUM
In the student activity demonstrating dynamic equilibrium using two measuring cylinders (1 and 2) and two glass tubes, what determines the final constant level of liquid in the two cylinders when transfer equilibrium is reached?
Read answer →Chemistry · EQUILIBRIUM
Consider the following statements regarding solubility product (\( K_{\text{sp}} \)) and precipitation: (A) For a salt of general formula \( \text{M}_x\text{X}_y \), the solubility product is given by \( K_{\text{sp}} = x^x y^y S^{x+y} \). (B) Passing \( \text{HCl} \) gas through saturated \( \text{NaCl} \) solution causes precipitation of pure \( \text{NaCl} \) due to the common ion effect. (C) Precipitation occurs when the ionic product is less than the solubility product (\( Q_{\text{sp}} < K_{\text{sp}} \)). (D) For a saturated solution of \( \text{BaSO}_4 \), the condition \( K_{\text{sp}} = [\text{Ba}^{2+}][\text{SO}_4^{2-}] \) holds true. Choose the correct answer from the options given below:
Read answer →Chemistry · EQUILIBRIUM
Match List-I (Equilibrium Reaction) with List-II (Relationship between \( K_p \) and \( K_c \)): List-I List-II A \( \text{H}_2(\text{g}) + \text{I}_2(\text{g}) \rightleftharpoons 2\text{HI}(\text{g}) \) I \( K_p = K_c (RT)^{-2} \) B \( \text{N}_2(\text{g}) + 3\text{H}_2(\text{g}) \rightleftharpoons 2\text{NH}_3(\text{g}) \) II \( K_p = K_c \) C \( 2\text{NOCl}(\text{g}) \rightleftharpoons 2\text{NO}(\text{g}) + \text{Cl}_2(\text{g}) \) III \( K_p = K_c (RT)^{-1} \) D \( 2\text{SO}_2(\text{g}) + \text{O}_2(\text{g}) \rightleftharpoons 2\text{SO}_3(\text{g}) \) IV \( K_p = K_c (RT)^1 \) Choose the correct answer from the options given below:
Read answer →Chemistry · EQUILIBRIUM
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): For ice-water equilibrium at \( 273\text{ K} \) and \( 1\text{ atm} \) in a thermos flask, the mass of ice and water remains constant over time. Reason (R): At equilibrium, both the melting of ice and freezing of water occur simultaneously at the exact same rate. In the light of the above statements, choose the correct answer from the options given below:
Read answer →Chemistry · EQUILIBRIUM
A sparingly soluble salt \( \text{A}_2\text{X}_3 \) has a solubility product \( K_{sp} = 1.08 \times 10^{-23} \) at 298 K. The molar concentration of \( \text{A}^{3+} \) ions in its saturated aqueous solution is:
Read answer →Chemistry · EQUILIBRIUM
In the heterogeneous equilibrium \( \text{Ni}(\text{s}) + 4\text{CO}(\text{g}) \rightleftharpoons \text{Ni}(\text{CO})_4(\text{g}) \), which expression represents the equilibrium constant \( K_c \)?
Read answer →Chemistry · EQUILIBRIUM
If the molar solubility of zirconium phosphate, \( \text{Zr}_3(\text{PO}_4)_4 \), in pure water is \( S \text{ mol L}^{-1} \), its solubility product \( K_{\text{sp}} \) is given by:
Read answer →Chemistry · EQUILIBRIUM
Calculate the percent dissociation of a \( 0.08\text{ M} \) hypochlorous acid (\( \text{HOCl} \)) solution if its ionization constant \( K_a \) is \( 2.5 \times 10^{-5} \).
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Radioactive sugar is added to a saturated aqueous solution of non-radioactive sugar that is in contact with undissolved solid sugar crystals at constant temperature. After some time, radioactivity is detected in both the solution and the solid sugar. What does this observation directly prove?
Read answer →Chemistry · EQUILIBRIUM
The ionization constant of a weak base \( \text{NH}_3 \) is \( 1.77 \times 10^{-5} \) at \( 298\text{ K} \). What is the ionization constant (\( K_a \)) of its conjugate acid \( \text{NH}_4^+ \)? (Given: \( K_w = 1.0 \times 10^{-14} \))
Read answer →Chemistry · EQUILIBRIUM
Initially, \( 3.00\text{ mol} \) of \( \text{PCl}_5 \) is kept in a \( 1\text{ L} \) closed reaction vessel at \( 380\text{ K} \). It dissociates as \( \text{PCl}_5(\text{g}) \rightleftharpoons \text{PCl}_3(\text{g}) + \text{Cl}_2(\text{g}) \) with \( K_c = 1.80 \). At equilibrium, what is the concentration of \( \text{PCl}_5 \)?
Read answer →Chemistry · EQUILIBRIUM
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): Addition of a catalyst to a reversible reaction does not change the equilibrium composition of the reaction mixture. Reason (R): A catalyst increases the rates of both forward and reverse reactions that pass through the same transition state by lowering the activation energy equally. In the light of the above statements, choose the correct answer from the options given below:
Read answer →Chemistry · EQUILIBRIUM
Given below are two statements: Statement I: A liquid with a higher equilibrium vapour pressure at a given temperature is more volatile and has a lower normal boiling point. Statement II: The equilibrium vapour pressure of water in a closed container increases with an increase in temperature. In the light of the above statements, choose the most appropriate answer from the options given below:
Read answer →Chemistry · EQUILIBRIUM
At \( 1100\text{ K} \), the thermal decomposition of calcium carbonate \( \text{CaCO}_3(\text{s}) \rightleftharpoons \text{CaO}(\text{s}) + \text{CO}_2(\text{g}) \) has an equilibrium pressure of \( \text{CO}_2 \) equal to \( 2.0 \times 10^5\text{ Pa} \). In standard state pressure (\( 1\text{ bar} = 10^5\text{ Pa} \)), the dimensionless value of \( K_p \) is:
Read answer →Chemistry · EQUILIBRIUM
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): For a saturated solution of barium sulphate, the solubility product is given by \( K_{\text{sp}} = [\text{Ba}^{2+}][\text{SO}_4^{2-}] \). Reason (R): Salts having molar solubility less than \( 0.01\text{ M} \) are classified as sparingly soluble salts. In the light of the above statements, choose the correct answer from the options given below:
Read answer →Chemistry · EQUILIBRIUM
