Electrochemistr...

Q. Cl₂ gas is passed into a solution containing KF, Kl and KBr, and CHCI₃ is added. There is a colour in CHCI₃ (lower) layer. It is due to 

Select the correct statement(s) about galvanic cell (Daniell cell) with E^° _cell​ = 1.10 V

Given, 

E° _Ag⁺/Ag = 0.80 V
E° _Mg²⁺/Mg = -2.37 V
E° _Cu²⁺/Cu = + 0.34V 
E° _Hg²⁺/Hg = 0.79V

Q.

Which of the following statement(s) is/are correct?

One mole of Ag₂CO₃ is strongly heated in an open vessel. Residue wll be 

Zinc ,silver and iron plates are dipped in CuSO₄ solutions placed in different vessels as shown:

Blue colour of CuSO₄ fades in  

For the following half -cell reactions ,E° values are:

Mn²⁺(aq) + 2H₂O(l)  MnO₂(s) + 4H⁺(aq) + 2e^-, E⁰ = -1.23V

MnO^-₄ (aq) + 4H+(aq) +3e^-  MnO₂(s) + 2H₂O(l), E⁰ = +1.70 V

 Thus  

Which of the following statement is correct?

 
Then

Consider some facts about Standard Hydrogen Electrode(SHE).

I. It is assigned a zero potential at all temperature corresponding to the reaction.

II. Platinum electrode coated with platinum black is dipped in acidic solution and H₂ gas is bubbled through it.
III. Concentration of both are oxidised and reduced forms of hydrogen is maintained at unity.

 Select the correct facts

The gas X at 1 atm is bubbled through a solution containing a mixture of 1 M Y^- and 1 M Z^- at 298 K.If the standard reduction potential

then,

The standard reduction potential values of three metallic cations X, Y, Z are 0.52, -3.03 and -1.18 V respectively. The order of reducing power of the corresponding metals is

A solution containing one mole per litre each of Cu(NO₃)₂ ,AgNO₃ ,Hg₂(NO₃)₂ and Mg(NO₃)₂ is being electrolysed using inert electrodes. The value of standard redution potentials are

with increasing voltage , the sequence of deposition of metals on the cathode will be

The standard reduction potentials at 298K for the following half-cell are given

Which is the strongest reducing agent?

The E^o _{M³⁺/M²⁺} values for Cr, Mn, Fe and Co are - 0.41 V, +1,57 V, + 0.77 V and m /m 1.97 V respectively. For which one of these metals the change in oxidation state from +2 to +3 is easiest?

Given the standard electrode potentials  

I. K⁺/K = -2.93V,
II. Ag⁺/Ag = 0.80V,
III. Hg^2+/Hg = 0.79 V 
IV. Mg²⁺/Mg = -2.37V,
V. Cr³⁺/Cr = - 0.74 V

These metals are arranged in increasing reducing power as

Statement Type

Direction : This section is based on Statement I and Statement II. Select the correct answer from the codes given below.

Statement I : CuSO₄ can be stored in a vessel made of zinc.

Statement II :  w.r.t SHE   

Statement I​ : When AgNO₃ solution is stirred with a spoon made of copper,solution turns blue.

Statement II : In electrochemical series ,copper is above silver

The positive value of the standard electrode potential of Cu²⁺/Cu,

(E°_Cu²⁺/Cu = 0.34 V) indicates that

In an electrolytic cell cathode acts as:

The electric charge for electrode deposition of 1gm. Equivalent of a substance is:

Matching List Type

Choices for the correct combination of elements from Column I and Column II are given as options (a), (b), (c) and (d), out of which one is correct

Match the half-cell reaction in Column I with their values in Column II and select the answer from the answer codes at the end.

Passage I 

The most stable oxidised species is

Passage I 

Reducing power of different species is in the order

Passage II 

Accidently chewing of a stray fragment of aluminium foil can cause a sharp tooth pain if the aluminium comes in contact with an amalgam filling. This filling, an alloy of silver, tin and mercury acts as the cathode (of a tiny galvanic cell), the aluminium as anode and saliva (of mouth) serves as electrolyte. When the aluminium and the filling come in contact, an electric current passes from aluminium to the filling, which is sensed by a nerve in the teeth.

Q.

Net reaction taking place when amalgam is in contact with aluminium foil is

Passage II 

Accidently chewing of a stray fragment of aluminium foil can cause a sharp tooth pain if the aluminium comes in contact with an amalgam filling. This filling, an alloy of silver, tin and mercury acts as the cathode (of a tiny galvanic cell), the aluminium as anode and saliva (of mouth) serves as electrolyte. When the aluminium and the filling come in contact, an electric current passes from aluminium to the filling, which is sensed by a nerve in the teeth.

Q.

Standard emf experienced by the person with dental filling is    

Passage III

When suspected drunk drivers are tested with a breathalyser, the alcohol (ethanol) in the exhaled breath is oxidised to ethanoic acid with an acidic solution of potassium dichromate.

Q.

Under standard state, E^°_cell of the breathalyser would be  

Passage III

When suspected drunk drivers are tested with a breathalyser, the alcohol (ethanol) in the exhaled breath is oxidised to ethanoic acid with an acidic solution of potassium dichromate.

Q.

Under the condition of unit activity of each species,emf recorded in the breathalyser at pH 4 would be  

The cathode in the central compartment of Castner Kellner cell used for the manufacture of NaOH is: