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Physical Chemistry

Oxidation Number or Oxidation State

Science > Chemistry > Redox Reactions > Oxidation Number or Oxidation State Oxidation Number OR Oxidation State: The donation of electrons is called the oxidation and the gain of electrons is called the reduction. Oxidation and reduction can further be explained by a knowledge of “Oxidation number”. The oxidation state of an atom in its […]

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Physical Chemistry

Introduction to Redox Reactions

Science > Chemistry > Redox Reactions > Introduction to Redox Reactions In this article we shall study about redox reactions, in which both the oxidation and reduction reactions take place simultaneously. Oxidation: Old Concept: It is a process in which addition of oxygen takes place. 2Mg + O2  →      2MgO It is a […]

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Physical Chemistry

Electrochemical Series and its Applications

Science > Chemistry > Electrochemistry > Electrochemical Series A series of electrodes or half cells arranged in order of their increasing standard oxidation potentials or in the decreasing order of their standard reduction potentials is called an electromotive force series or electrochemical series. Electrochemical series is also known as e.m.f. series Characteristics Electrochemical Series: In […]

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Physical Chemistry

Use of Nernst Equation

Science > Chemistry > Electrochemistry > Use of Nernst Equation In this article, we shall study the use of the Nernst equation to find e.m.f. of cell and electrodes. Convention Followed While Calculation of Cell Potential (e.m.f.): In the symbolic representation of the cell, the right-hand side electrode is the cathode (positive electrode) and the […]

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Physical Chemistry

Concept of Electrode Potential: Nernst Theory

Science > Chemistry > Electrochemistry > Nernst Theory In this article, we shall study the Nernst theory of electrode potential, Nernst equation, and its use. Single Electrode or Half cell or Electrode Couple: A single electrode or half cell or electrode couple is produced when a metal is dipped in the solution of its own […]

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Physical Chemistry

Types of Electrodes

Science > Chemistry > Electrochemistry > Types of Electrodes In this article, we shall study different types of electrodes, their representation, writing cell reactions, and finding e.m.f. of a cell. There are four types of electrodes Gas electrodes Metal–sparingly soluble metal salt electrodes Metal – metal ion electrodes Redox Electrodes Gas Electrodes: A gas electrode […]

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Physical Chemistry

Reference Electrodes

Science > Chemistry > Electrochemistry > Reference Electrodes The electrode whose potential is arbitrarily fixed or is exactly known at a given constant temperature is known as a reference electrode. Using reference electrodes unknown potential of any other single electrode can be found out e.g. two commonly used reference electrodes are standard hydrogen electrode (SHE) […]

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Physical Chemistry

Representation of Electrochemical Cell

Science > Chemistry > Electrochemistry > Representation of Electrochemical Cell In this article, we shall study the representation of cell using conventions on paper. We shall also discuss the construction and working of the salt bridge. Electrochemical (Voltaic or Galvanic) cell consists of two half cells. In one half-cell, an oxidation reaction takes place and […]

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Physical Chemistry

Secondary Electrochemical Cells

Science > Chemistry > Electrochemistry > Secondary Electrochemical Cells In this article, we shall study the construction and working of lead accumulator, and Ni-Cd cells. Lead Accumulator: A lead accumulator is a secondary cell because electrical energy is not generated within the cell itself but it is previously stored in it from the external source. […]

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Physical Chemistry

Primary Electrochemical Cells

Science > Chemistry > Electrochemistry > Primary Electrochemical Cells Types of Electrochemical Cell: An electrochemical cell is a device which is used to generate electrical energy at the expense of spontaneous oxidation-reduction reaction. An electrochemical cell is also known as a galvanic cell or a voltaic cell.  In an electrochemical cell, chemical energy is converted into […]