For the following concentration cell, to be spontaneous Pt(H2)P1 atm. |HCl | Pt(H2)P2 atm. Which of the following is correct?
P1=P2
P1<P2
P1>P2
Can't be predicted
The standard oxidation potential E° for the half cell reaction are
- 0.35 V
+ 0.35 V
0.17V
1.17V.
To observe the effect of concentration on the conductivity of electrolytes of different nature were taken in two vessels A and B. A contains weak electrolyte NH4OH and B contains strong electrolyte NaCl. In both containers, concentration of respective electrolyte was increased and conductivity observed
in A conductivity increases, in B conductivity decreases
in A conductivity decreases, while in B conductivity increases
in both A and B conductivity increase
in both A and B conductivity decreases.
Anode in the galvanic cell is :
negative electrode
positive electrons
neutral electrode
none of the above
When Cu reacts with AgNO3 solution , the reaction takes place is :
Oxidation of Cu
Reduction of Cu
Oxidation of Ag
Reduction of NO3-
The products formed when an aqueous solution of NaBr is electrolysed in a cell having inert electrodes are
Na and Br2
Na and O2
H2, Br2 and NaOH
H2 and O2.
Ionic mobility of Ag+ is (Ag+ = 5 x 10-1 ohm-1 cm2 eq-1) :
5.2 x 10-9
2.4 x 10-9
1.52 x 10-9
8.25 x 10-9
The chemical reaction,
2AgCl (s) + H2 (g) → 2HCl (aq) + 2Ag (s)
taking place in a galvanic cell is represented by the notation
Pt(s)| H2 (g), 1 bar | 1 M KCl (aq) | AgCl (s) | Ag (s)
Pt(s)| H2 (g), 1 bar | 1 M HCl (aq) | 1M Ag+(aq) | Ag (s)
Pt(s)| H2 (g), 1 bar | 1 M HCl (aq) | AgCl (s) | Ag (s)
Pt(s)| H2 (g), 1 bar | 1 M KCl (aq) | Ag (s) | AgCl (s)
Assertion: For the Daniel cell, Zn/Zn2+||Cu2+|Cu with Ecell= 1.1V, application of opposite potential greater than 1.1 V results into flow of electron from cathode to anode.
Reason : Zn is deposited at anode and Cu is dissolved at cathode.
If both assertion and reason are true and reason is the correct explanation of the assertion.
If both assertion and reason are true but reason is not the correct explanation of the assertion.
If assertion is true, but reason is false.
Both assertion and reason are false statements.
B.
If both assertion and reason are true but reason is not the correct explanation of the assertion.
If the opposing potential becomes slightly larger than that of the cell, the direction of current flow is reversed, and so is the cell reaction. Now zinc ions are converted to zinc at one electrode and Cu is converted into copper ion and the overall cell reaction becomes
Zn2+ + Cu Zn + Cu2+