NCERT Solution Class 11th Chemistry Chapter – 8 Redox Reactions Notes

NCERT Solution Class 11th Chemistry Chapter – 8 Redox Reactions

NCERT Solution Class 11th Chemistry Chapter – 8 Redox Reactions Notes Oxidation, Reduction, Redox Reaction discuss Redox Reactions Notes. 

NCERT Solution Class 11th Chemistry Chapter – 8 Redox Reactions

Chapter – 8

Redox Reactions

Notes

Reactions taking place in an electrochemical cell are redox reactions in nature.

In an electrochemical cell loss of free energy appears as electrical energy.

The reaction in an electrochemical cell is spontaneous in nature.

A salt bridge maintains the electrical neutrality of the two electrolytes in their half cells.

The e.m.f. of an electrochemical cell is E°_cathode — E°_anode cathode anode

According to the electronic concept, the loss of electron is oxidation, and the gain of the electron is reduced.

The oxidation number of free elements homo atomic molecules and also of the neutral molecule is zero.

Electrolysis is the migration of the ions of the electrolyte towards the oppositely charged electrode when the current is passed.

In an electrolytic cell, the redox reaction is non-spontaneous in nature.

The chemical energy of the redox reaction occurring in the galvanic cell is converted into electrical energy.

Electrons flow from anode to cathode in the external circuit while current flow from cathode to anode.

95600 c of charge represents one Faraday.

Oxidation – Oxidation is a process in which an atom or ion loses an electron(s).

Reduction – Reduction is a process in which an atom or ion gains an electron(s).

Oxidizing agent – (Oxidant) is a species that can readily accept one or more electrons.

Reducing agent – (Reductant) is a species that readily lose one or more electrons.

Redox Reaction – Redox reaction is a chemical reaction in which oxidation and reduction occur simultaneously.

Electrochemical cell – Electrochemical cell is a device in which oxidation and reduction half-reactions are carried indirectly and the loss of chemical energy during the reaction appears as electrical energy.

Electrolytic cell – Electrolytic cell is a device in which electrical energy is supplied from an external source to bring about a chemical reaction.

Anode – Anode is an electrode where the electrons are released or where oxidation takes place.

Cathode – A cathode is an electrode where the electrons are accepted or where reduction takes place.

Half cell – A half cell is a portion of an electrochemical cell in which either oxidation or reduction takes place.

Standard hydrogen electrode – Standard hydrogen electrode is an electrode that is used to calculate the reduction potential of another electrode. Its own reduction potential is taken as zero.

Standard reduction potential – Standard reduction potential of an electrode is its reduction potential as compared to that of a standard hydrogen electrode which is taken as zero.

Salt bridge – Salt bridge is an inverted U-shaped glass tube that contains a suitable electrolyte and connects the two-half cells in an electrochemical cell.

E.m.f. of a cell – E.m.f. of a cell is the difference between the reduction potential of electrodes when the cell is not sending the current.

Potential difference – Potential difference is the difference of potential between two electrodes when the cell is sending currents.

Electro-chemical series – Electrochemical series is the series obtained by arranging the electrode in order of increasing standard reduction potential values.

Electrolyte – Electrolyte is a substance that is capable of conducting electricity either in a molten state or when dissolved in an aqueous solution.

Electrolysis – Electrolysis is the process of the decomposition of an electrolyte on passing electric current.

Oxidation Number – The oxidation number of an element is the residual charge which its atom appears to have when all other atoms present in its combination are removed as ions.

Disproportionation Reaction – In this reaction, an element in one oxidation state is simultaneously oxidized and reduced.

Redox couple – A redox couple consists of the oxidized and reduced forms of the same substance taking part in an oxidation and reduction half-reaction.