Recent questions tagged ch3

The number of all possible matrices of order 3 x 3 with each entry 0 or 1 is?

asked Feb 18, 2014 by balaji.thirumalai

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The Edison storage cell is represented as $Fe(s)/FeO(s)/KOH(aq)/Ni_2O_3(s)/Ni(s)$.The half cell reactions are $Ni_2O_3(s)+H_2O(l)+2e^-\rightarrow 2NiO(s)+2OH^-(aq)\Rightarrow E^0=0.4V$,$FeO(s)+H_2O(l)+2e^-\rightarrow Fe(s)+2OH^-(aq)\Rightarrow E^0=-0.87.V$.What will be the maximum amount of electrical energy that can be obtained from one mole of $Ni_2O_3$

asked Feb 18, 2014 by sreemathi.v

1 answer

The Edison storage cell is represented as $Fe(s)/FeO(s)/KOH(aq)/Ni_2O_3(s)/Ni(s)$.

asked Feb 18, 2014 by sreemathi.v

1 answer

$H_2O_2$ can be prepared by successive reactions

asked Feb 18, 2014 by sreemathi.v

1 answer

The voltage of cell given is -0.46V $Pt/H_2$(atm)/$NaHSO_3(0.4M),Na_2SO_3(6.44\times 10^{-3}M)\parallel Zn^{+2}(0.3M)/Zn(g)$.Also $Zn^{+2}+2e^-\rightarrow Zn(s) \leftrightharpoons E^0=-0.763$V.Then the value of $K_2=\large\frac{[H^+][SO_3^{-2}]}{[HSO_3^-]}$

asked Feb 18, 2014 by sreemathi.v

1 answer

1.26gm weight of NaOH required to be added in R.H.S to consume all the $H^+$ present in R.H.S of cell of emf to .701V at $25^{\large\circ}C$.Given: $Zn/Zn^{+2}(0.1M)\parallel HCl$(1litre)$/H_2/$(1atm)/P:-$E^0_{Zn/Zn^{+2}}=0.7602$.The emf of cell after addition of NaOH will be

asked Feb 18, 2014 by sreemathi.v

1 answer

Calculate the minimum weight of NaOH required to be added in R.H.S to consume all the $H^+$ present in R.H.S of cell of emf to .701V at $25^{\large\circ}C$.Given: $Zn/Zn^{+2}(0.1M)\parallel HCl$(1litre)$/H_2/$(1atm)/P:-$E^0_{Zn/Zn^{+2}}=0.7602$

asked Feb 18, 2014 by sreemathi.v

1 answer

Given the overall formation constant of the $[Fe(CN)_6]^{-4}$ ion as $10^{35}$ and the standard potential for half reaction $Fe^{+3}+e^-\leftrightharpoons Fe^{+2},E^0=0.77V$,$[Fe(CN)_6]^{-3}+e^-\leftrightharpoons [Fe(CN)_6]^{-4},E^0=0.36V$.Then the overall formation constant of $[Fe(CN)_6]^{-3}$ ion is

asked Feb 18, 2014 by sreemathi.v

1 answer

The EMF of cell Hg/mercurous nitrate (0.01M)$\parallel$ mercurous nitrate (0.1M)/Hg was found to be 0.0295V at $25^{\large\circ}C$ .Then molecular formula of mercurous nitrate is

asked Feb 18, 2014 by sreemathi.v

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From following molar conductivities at infinite dilution $\Lambda_m^{\large\circ}$ for $Ba(OH)_2=457.6\Omega^{-1}cm^2mol^{-1}$,$\Lambda_m^{\large\circ}$ for $BaCl_2=240.6\Omega^{-1}cm^2mol^{-1}$,$\Lambda_m^{\large\circ}$ for $NH_4Cl=129.8\Omega^{-1}cm^2mol^{-1}$.The $\Lambda_m^{\large\circ}$ for $NH_4OH$ is

asked Feb 18, 2014 by sreemathi.v

1 answer

Calculate EMF of concentration cell consisting of zinc electrodes,one immersed in a solution of 0.01M $Zn^{+2}$ ions and the other in a solution of 0.1M $Zn^{+2}$ ions at $25^{\large\circ}C$.The two solution are separated by a salt bridge

asked Feb 18, 2014 by sreemathi.v

1 answer

The EMF of electrode -concentration cell $Zn-Hg(C_1)/Zn^{+2}(aq)/Zn-Hg(C_2)$ at $25^{\large\circ}C$ if the concentration of zinc amalgam are $C_1=2g$ per 100g of mercury and $C_2=1g$ per 100g of mercury.

asked Feb 18, 2014 by sreemathi.v

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For the following galvanic cell the emf will be at $25^{\large\circ}C$.$Ag/AgCl(s),KCl(0.2M\parallel KBr(0.001M).AgBr(s)/Ag$.The solubility product of $AgCl$ & $AgBr$ are $2.8\times 10^{-10}$ and $3.3\times 10^{-13}$ respectively.

asked Feb 18, 2014 by sreemathi.v

1 answer

The standard reduction potential of $Ag^+/Ag$ electrode at 298K is 0.79V.$K_{sp}$ of Ag$^+$ is $8.7\times 10^{-17}$.Evaluate the standard reduction potential of $I^-/AgI/Ag$ electrode

asked Feb 18, 2014 by sreemathi.v

1 answer

The half potential of $Cl^{-1}(C_1)/AgCl/Ag$ electrode.Given the value of $E^0$ for $Ag^++e^-\rightarrow Ag$ and $K_{sp}$ of AgCl is

asked Feb 18, 2014 by sreemathi.v

1 answer

The emf of cell $Zn/ZnCl_2(0.05mol\;dm^{-3})/Ag^+/AgCl(s)/Ag$ is 1.015V at 298K,the silver electrode being positive,while the temperature coefficient of its emf is $-0.00492VK^{-1}$.Write down the equation for reaction occuring when the cell is allowed to discharge and calculate changes in entropy (s) accompanying this reaction,at 298K?

asked Feb 18, 2014 by sreemathi.v

1 answer

The emf of cell $Zn/ZnCl_2(0.05mol\;dm^{-3})/Ag^+/AgCl(s)/Ag$ is 1.015V at 298K,the silver electrode being positive,while the temperature coefficient of its emf is $-0.00492VK^{-1}$.Write down the equation for reaction occuring when the cell is allowed to discharge and calculate changes in free energy(G)?

asked Feb 18, 2014 by sreemathi.v

1 answer

Consider the relation,$2Ag^++Cd\rightarrow 2Ag+Cd^{+2}$ the standard electrode potentials for $Ag^+/Ag$ and $Cd^{+2}/Cd$ couples $0.8\;V$ and $0.04\;V$ respectively Then the emf of given reaction will be (if $[Cd^{+2}]=0.1M,[Ad^+]=1M)$

asked Feb 18, 2014 by sreemathi.v

1 answer