Recent questions in Chemistry

Refer the below :

asked Feb 19, 2014 by sreemathi.v

1 answer

In the below reaction the product Y is

asked Feb 19, 2014 by sreemathi.v

1 answer

The below reaction involves

asked Feb 19, 2014 by sreemathi.v

1 answer

The correct order of reactivities of nucleophilic addition across -C=O of the RCOR ,RCHO and ArCHO is

asked Feb 19, 2014 by sreemathi.v

1 answer

Which of the following species is an intermediate in the reaction shown below :

asked Feb 19, 2014 by sreemathi.v

1 answer

The reduction at acetone with magnesium amalgam followed by hydrolysis produces

asked Feb 19, 2014 by sreemathi.v

1 answer

The haloform reaction is not shown by the compound

asked Feb 19, 2014 by sreemathi.v

1 answer

Refer the below reaction :

asked Feb 19, 2014 by sreemathi.v

1 answer

Refer the below :

asked Feb 19, 2014 by sreemathi.v

1 answer

Which of the following compounds does not under go aldol condensation?

asked Feb 19, 2014 by sreemathi.v

1 answer

Which of the following statements regarding aldehyde is not correct?

asked Feb 19, 2014 by sreemathi.v

1 answer

The cannizzaro reaction is not given by

asked Feb 18, 2014 by sreemathi.v

1 answer

In the Cannizzaro reaction given : $2C_6H_5-CHO\quad \underrightarrow {OH^-}\quad C_6H_5-CH_2OH +C_6H_5COO^-$ the slowest step is

asked Feb 18, 2014 by sreemathi.v

1 answer

Which of the following is an example of aldol condensation?

asked Feb 18, 2014 by sreemathi.v

1 answer

Which of the following compound is expected to have maximum enol content in ethanol?

asked Feb 18, 2014 by sreemathi.v

1 answer

The reaction $CH_3COCH_3 \large\xrightarrow{[H^+]} CH_3CH_2CH_3$ is known as

asked Feb 18, 2014 by sreemathi.v

1 answer

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

1 answer

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

If the radius of $Cs^+$ is 169pm and that of $Cl^-$ is 181pm then find the co-ordination number of $Cs^+$

asked Feb 18, 2014 by sharmaaparna1

1 answer

How many number of atoms are there in a cube based unit cell having one atom each corner and two atoms on each body diagonal of cube ?

asked Feb 18, 2014 by sharmaaparna1

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

1 answer

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

Consider the relation,$2Ag^++Cd\rightarrow 2Ag+Cd^{+2}$ the standard electrode potentials for $Ag^+/Ag$ and $Cd^{+2}/Cd$ couples 0.8V and 0.04V respectively.What is the standard potential for this reaction?

asked Feb 18, 2014 by sreemathi.v

1 answer

An electric current is passed through two electrolytic cells connected in series.One containing a solution of silver nitrate and the other solution of $H_2SO_4$.What volume of oxygen measured at $25^{\large\circ}C$ and 750mm of Hg would be liberated from $H_2SO_4$ if $8\times 10^{22}$ ions of $Ag^+$ are deposited from the silver nitrate solution?

asked Feb 17, 2014 by sreemathi.v

1 answer

An electric current is passed through two electrolytic cells connected in series.One containing a solution of silver nitrate and the other solution of $H_2SO_4$.What volume of oxygen measured at $25^{\large\circ}C$ and 750mm of Hg would be liberated from $H_2SO_4$ if 1mole and of $Ag^+$ are deposited from silver nitrate solution?

asked Feb 17, 2014 by sreemathi.v

1 answer

In an electrolysis experiment electric current was passed for 5hr through two cells connected in series.The first cell contains gold salt and second contains $CuSO_4$ solution.9.83g of gold was deposited in first cell.The magnitude of current in amperes is :-

asked Feb 17, 2014 by sreemathi.v

1 answer

In an electrolysis experiment electric current was passed for 5hr through two cells connected in series.The first cell contains gold salt and second contains $CuSO_4$ solution.9.83g of gold was deposited in first cell.If the oxidation number of Au is +3,find the amount of copper deposited in second cell

asked Feb 17, 2014 by sreemathi.v

1 answer

The passage of a constant current through a dilute solution of sulfuric acid with platinum electrodes,for the resulted in liberation of 336ml of mixed hydrogen and oxygen ,reduced to S.T.P.Then the strength of current is

asked Feb 17, 2014 by sreemathi.v

1 answer

$CuSO_4$ solution(250ml) was electrolysed using a platinum anode and a copper cathode.At constant current of 2mA was passed for 16 minutes.It was found that after electrolysis the absorbance of this solution was reduced to 50% of its original value.Then the concentration of copper sulphate in solution to begin with is

asked Feb 17, 2014 by sreemathi.v

1 answer

The standard reduction potential of $Cu^{+2}/Cu$ and $Ag^+/Ag$ electrode are 0.337 and 0.799Volt respectively for this positive emf galvanic cell,for what concentration of $Ag^+$ will be emf of cell at $25^{\large\circ}C$ be zero,if the concentration of $Cu^{+2}$ is 0.01M?

asked Feb 17, 2014 by sreemathi.v

1 answer

A zinc rod is placed in $0.1\;M$ solution of $ZnSO_4$ at $25^{\large\circ}$C.Assuming that the salt is dissociated to the extent of $95\%$ at this dilusion ,then the potential of electrode at this temperature.Given that $E^0_{Zn^{2+}/Zn}=0.76Volts$.

asked Feb 17, 2014 by sreemathi.v

1 answer

A solution of a salt of a metal of atomic weight $'\lambda'$ was electrolysed for 150minutes with 0.15A of current .The weight of metal deposited was 0.783g.Find X,the specific heat of metal=0.057Cal/$g^{\large\circ}C$.According to Dulong-Petit's law,approximate atomic weight of a metal $X$ specific heat=6.4

asked Feb 17, 2014 by sreemathi.v

1 answer

The EMF of cell is : $Pt/H_2/CH_3COOH(0.1M)\parallel NH_4OH(0.01M)/H_2/Pt$.$K_a$ for $CH_3COOH=1.8\times 10^{-5}$ and $K_b$ for $NH_4OH=1.8\times 10^{-5}$

asked Feb 17, 2014 by sreemathi.v

1 answer

In which of the following crystals alternate tetrahedral voids are occupied

asked Feb 17, 2014 by sharmaaparna1

1 answer

In a solid AB having the NaCl structure A atoms occupy the corners of the cubic unit cell . If all the faces centred atoms along one of the axis are removed then the resultant stoichiometry of the solid is

asked Feb 17, 2014 by sharmaaparna1

2 answers

EMF of following cell is 0.67V at 298K $Pt/H_2(1atm)/H^+(pH=X)\parallel KCl(1N)/Hg_2Cl_2(s)/Hg$.Calculate pH of anode compartment.Given : $E^0_{Cl^-/Hg^2Cl_2/Hg}=0.28V$.

asked Feb 17, 2014 by sreemathi.v

1 answer

The co-ordination number of metal crystallizing in a structure adopting hexagonal close packing is

asked Feb 17, 2014 by sharmaaparna1

1 answer

Ask Questions, Get Answers