Download App

Electrochemistry — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistryElectrochemistry3 Marks
Question
Explain types of Electrodes with examples
✓

Answer

(1) Active electrode :
→ The active electrodes of metal are like Zn, Ni, Cu, Ag etc.
→ Atoms of this kind of electrode undergo oxidation or reduced.
$\begin{array}{l} Zn \rightarrow Zn ^{2+}+2 e ^{-} \text {(oxidation) }
\\ Cu ^2++2 e ^{-} \rightarrow Cu \text { (reduction) }\end{array}$
(2) Inert electrode :
→ Sometimes metals like platinum or gold are used as inert electrodes. They do not participate in the reaction but provide their surface for oxidation or reduction reactions and for the conduction of electrons.
→ For example, Pt is used in the following half cells:
Hydrogen electrode : $Pt ( s )\left| H _2(g)\right| H ^{+}( aq )$
with half-cell reaction: $H ^{+}( aq )+ e ^{-} \rightarrow \frac{1}{2} H _2(g)$
Bromine electrode : $Pt ( s )\left| Br _2( aq )\right| Br ^{-}( aq )$
with half-cell reaction : $\frac{1}{2} Br _2( aq )+ e ^{-} \rightarrow Br ^{-}( aq )$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "3 Marks Question" from Electrochemistry→Electrochemistry — all question types→Chemistry STD 12 Science question papers→Gujarat Board STD 12 Science question papers→Gujarat Board question paper generator→

Similar questions

Write the IUPAC names of the following coordination compounds:
  1. [Cr(NH3)3cl3]
  2. K3[Fe(CN)6]
  3. [CoBr2(em)2]+, (en= ethylenediamine)
→
Explain the following cases giving appropriate reasons: 
  1. Nickel does not form low spin octahedral complexes.
  2. The $\pi$-complexes are known for the transition metals only.
  3. Co2+ is easily oxidised to Co3+ in the presence of a strong ligand.
→
How many mL of 0.1 M HCl are required to react completely with 1 g mixture of Na2CO3 and NaHCO3 containing equimolar amounts of both?
→
For the first order thermal decomposition reaction, the following data were obtained:
$\text{C}_{2}\text{H}_{5}\text{Cl}\text{(g)}\rightarrow \text{C}_{2}\text{H}_{4}\text{(g)} + \text{HCl}\text{(g)} $
Time/sec Total pressure/atm
0 0.30
300 0.50
Calculate the rate constant
(Given: log 2 = 0.301, log 3=0.4771, log 4 =0.6021)
→
Calculate the amount of benzoic acid (C6H5COOH) required for preparing 250 mL of 0.15 M solution in methanol.
→
Permanganate ion $\left( MnO _4^{-}\right)$gives different reduction products at different concentration of hydrogen ions, write their equations.
→
Write the structures of compounds A, B and C in the following reactions:
  1. $\text{CH}_3-\text{COOH}\xrightarrow{\text{ }\text{ }\text{ }\text{NH}_3/\triangle\text{ }\text{ }\text{ }}\text{A}\xrightarrow{\text{ }\text{ }\text{ }\text{Br}_2/\text{KOH(aq)}\text{ }\text{ }\text{ }}\text{B}\xrightarrow{\text{ }\text{ }\text{ }\text{CHCL}_3+\text{alc.KOH}\text{ }\text{ }\text{ }}\text{C}$
  1. $\text{C}_6\text{H}_5\text{N}_2^+\text{BF}_4^-\xrightarrow[\triangle]{\text{NaNO}_2/\text{Cu}\text{ }\text{ }}\text{A}\xrightarrow{\text{ }\text{ }\text{ }\text{Fe}/\text{HCL}\text{ }\text{ }\text{ }}\text{B}\xrightarrow{\text{ }\text{ }\text{ }\text{CH}_3\text{COCL}/pyridine\text{ }\text{ }\text{ }}\text{C}$
→
Write the Nernst equation and emf of the following cells at 298 K:
Mg(s) | Mg2+(0.001M) || Cu2+(0.0001 M) | Cu(s)
→
Write the structures of fragments produced on complete hydrolysis of DNA. How are they linked in DNA molecule? Draw a diagram to show pairing of nucleotide bases in double helix of DNA.
→
Match the properties given in Column I with the metals given in Column II.

 
Column I (Property)
 
Column II (Metal)
(i)
An element which can show +8 oxidation state
(a)
Mn
(ii)
3d block element that can show upto +7 oxidation state
(b)
Cr
(iii)
3d block element with highest melting point
(c)
Os
   
(d)
Fe

 

→