Problem 48
For the reaction \(\mathrm{X}+\mathrm{Y} \rightleftharpoons \mathrm{Z}\) \(\mathrm{K}_{\mathrm{C}}=6 \times 10^{-7} ;\) then at cquilibrium (1) \(\mathrm{Z}\) would be favourcd (2) X would be favoured (3) Both X and Y would be favoured (4) \(\mathrm{X}, \mathrm{Y}\) and \(\mathrm{Z}\) would be favoured
Problem 49
At \(25^{\circ} \mathrm{C}, \mathrm{K}_{\mathrm{C}}\) for the equilibrium \(2 \mathrm{O}_{3}(\mathrm{~g}) \rightleftharpoons 3 \mathrm{O}_{2}(\mathrm{~g})\) is \(5.5 \times 10^{57}\). This explains (1) the oxidizing power of ozone (2) the absence of detectable amounts of ozone in the lower atmospherc (3) the formation of ozonc laycr in the upper atmosphcre (4) the polluting nature of ozonc
Problem 50
For the reaction \(\mathrm{Ag}_{2} \mathrm{CO}_{3}(\mathrm{~s}) \rightleftharpoons \mathrm{Ag}_{2} \mathrm{O}(\mathrm{s})+\mathrm{CO}_{2}(\mathrm{~g})\) the value of the equilibrium constant \(\mathrm{K}_{\mathrm{p}}\) is \(3.16 \times 10^{3}\) atm at \(298 \mathrm{~K}\) and is \(1.48 \mathrm{~atm}\) at \(500 \mathrm{~K}\); then which one of the following statements is correct? (1) The yield of \(\mathrm{CO}_{2}\) is independent of temperature. (2) The yield of \(\mathrm{CO}_{2}\) will increase at high pressure. (3) The value of \(\Delta H\) for the forward reaction is negligible. (4) The forward reaction is endothermic.
Problem 51
The dissociation constants of two acids \(/ / A_{1}\), and \(/ I A_{2}\) are \(3.6 \times 10^{-4}\) and \(1.8 \times 10^{-5}\), respectively. The relative strengths of the acids will be (1) \(1: 4\) (2) \(4: 1\) (3) \(1: 16\) (4) \(16: 1\)
Problem 52
In the system \(\mathrm{CaF}_{2}(\mathrm{~s}) \rightleftharpoons \mathrm{Ca}^{2}+2 \mathrm{~F}^{-}\), if the con- centration of \(\mathrm{Ca}^{2}\) ions is increased by 4 times the equilibrium concentration of \(\mathrm{F}^{-}\) ions will change to (1) \(1 / 2\) of the initial value (2) \(1 / 4\) of the initial valuc (3) 2 times of the initial valuc (4) 4 times of the initial valuc
Problem 52
For an acid \(\mathrm{CH}_{3} \mathrm{COOH}+\mathrm{H}_{2} \mathrm{O} \rightleftharpoons \mathrm{CH}_{3} \mathrm{COO}^{-}+\mathrm{H}_{3} \mathrm{O}^{+} ; K_{1}\) and for a base \(\mathrm{CH}_{3} \mathrm{COO}^{-}+\mathrm{H}_{2} \mathrm{O} \rightleftharpoons \mathrm{CH}_{3} \mathrm{COOH}+\mathrm{OH} ; K_{2}\) Then (1) \(K_{1} \cdot K_{2}=K_{\mathrm{w}}\) (2) \(\log K_{1}+\log K_{2}=\log K_{\mathrm{w}}\) (3) \(\mathrm{p} K_{1}+\mathrm{p} K_{2}=\mathrm{p} K_{\mathrm{w}}\) (4) all are correct
Problem 53
Which of the following is correct? 1) \(K_{\mathrm{a}}\) (weak acid) \(\times K_{\mathrm{b}}\) (conjugate weak base) \(=K_{\mathrm{v}}\) 2) \(K_{\mathrm{a}}\) (strong acid) \(\times K_{\mathrm{b}}\) (conjugate strong base) \(=K_{\mathrm{w}}\) 3) \(K_{\mathrm{a}}\) (weak acid) \(\times K_{\mathrm{b}}\) (weak base) \(=K_{\mathrm{T}}\) 4) \(K_{\mathrm{a}}\) (weak acid) \(\times K_{\mathrm{b}}\) (conjugate strong base) \(=K_{\mathrm{w}}\)
Problem 53
In the case of \(\mathrm{PCl}_{5}(\mathrm{~g}) \rightleftharpoons \mathrm{PCl}_{3}(\mathrm{~g})+\mathrm{Cl}_{2}(\mathrm{~g})\) the degree of dissociation " \(x^{\prime \prime}\) is related to the equilibrium pressure \(P\) as (1) \(x \propto \frac{1}{P}\) (2) \(x \alpha \frac{1}{\sqrt{P}}\) (3) \(x \alpha P\) (4) \(x \alpha P^{2}\)
Problem 54
2 moles of \(\mathrm{PCl}_{5}\) were heated in a closed vessel of a 2 litre capacity. \(\Lambda\) t cquilibrium \(40 \%\) of \(\mathrm{PCl}_{5}\) dissociated into \(\mathrm{PCl}_{3}\) and \(\mathrm{Cl}_{2}\). The valuc of the equilibrium constant is (1) \(0.267\) (2) \(0.53\) (3) \(2.63\) (4) \(5.3\)
Problem 54
Consider the following reactions (i) \(\mathrm{CO}_{3}^{2-}+\mathrm{H}_{2} \mathrm{O} \rightleftharpoons \mathrm{HCO}_{3}^{-}+\mathrm{OH}^{-}\) (ii) \(\mathrm{CO}_{2}+\mathrm{H}_{2} \mathrm{O} \rightleftharpoons \mathrm{H}_{2} \mathrm{CO}_{3}\) (iii) \(\mathrm{NH}_{3}+\mathrm{H}_{2} \mathrm{O} \rightleftharpoons \mathrm{NH}_{4} \mathrm{OH}\) (iv) \(\mathrm{HCl}+\mathrm{H}_{2} \mathrm{O} \rightleftharpoons \mathrm{H}_{3} \mathrm{O}^{+}+\mathrm{Cl}^{-}\) Which pair of reactions proves that water is amphoteric? (1) \(i\) and ii (2) ii and iii (3) iii and iv (4) i and iii
