Electrochemistr...

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

Consider the following half-reactions:

Select the correct statements on the basis of the above data

Select the correct statement(s) based on the following half-reaction:

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  

E °values of Mⁿ⁺ + ne^-  →M are given below
Fe²⁺ /Fe -0.44 V, Mg²⁺ /Mg -2.37 V, Pt(H₂ )/H⁺ 0.00 V,
AI³⁺ /AI -1.66 V , Zn²⁺ /Zn - 0.76 V, Cu²⁺ /Cu +0.34 V,
Ag⁺ /Ag + 0.80 V, Ni²⁺ /Ni -0.26 V

How many of the metals can be used to prevent corrosion of Ni to Ni²⁺ ?