Half life period of a reaction is defined as the time during which the concentration of a reactant is reduced to half of its initial concentration. or The time in which half of a reaction is completed. It is generally denoted as t½ The half life period of a first order reaction may be calculated as given below: The first order rate equation for the reaction A … [Read more...] about Half Life Period of a Reaction
Class 12
Experimental Determination of Order of a Reaction
Experimental Determination of Order of a Reaction (1) Graphical method This method is used when there is only one reactant. It involves the following steps: 1) The concentrations of the reactants are measured by some suitable method. 2) A graph is plotted between concentration and time. 3) The instantaneous rates of the reaction at different times are calculated by … [Read more...] about Experimental Determination of Order of a Reaction
Integrated Rate Expression
Integrated Rate Expression The concentration dependence of rate is called differential rate equation. Integrated rate equation gives a relation between directly measured experimental quantities i.e. concentrations at different times. The integrated rate equations are different for reactions of different orders. The instantaneous rate of a reaction is given by differential … [Read more...] about Integrated Rate Expression
Molecularity of a Reaction
Molecularity of a Reaction For a chemical reaction to occur, the reacting molecules must collide with each other. The number of reacting species (molecules, atoms or ions) which collide simultaneously to bring about a chemical reaction is called molecularity of a reaction. If a reaction involves the decomposition of only a single species, the molecularity is one or it is … [Read more...] about Molecularity of a Reaction
Order of a Reaction
Order of a Reaction The order of a reaction is defined as: the sum of the powers to which the concentration terms are raised in the rate law equation to express the observed rate of the reaction. The power of the concentration of a particular reactant in the rate law is called the order of the reaction with respect to that reactant. If the rate of a reaction, aA + bB … [Read more...] about Order of a Reaction
Factors Influencing Rates of Chemical Reactions
Factors Influencing Rates of Chemical Reaction There are a number of factors which influence the rate of a reaction. Some of the important factors are: 1) Concentration of the reacting species. 2) Temperature of the system 3) Nature of the reactants and products. 4) Presence of a catalyst. 5) Surface area. 6) Exposure to radiation. 1) Concentration of the … [Read more...] about Factors Influencing Rates of Chemical Reactions
Rate of a Chemical Reaction
The feasibility of a reaction under the given experimental conditions can be predicted on, the basis of decrease in Gibbs energy (ΔG < 0). The extent to which a reaction proceeds can be explained with the help of equilibrium constant of the reaction. The branch of chemistry which deals with the rates of chemical reactions and the factors which influence the rates of … [Read more...] about Rate of a Chemical Reaction
Corrosion
Corrosion When metals are exposed to atmospheric conditions, they react with air or water in the environment to form undesirable compounds (usually oxides). This process is called corrosion. The least active metals such as gold, platinum and palladium are attacked by environment. For example: Silver tarnishes, copper develops a green coating, lead or stainless steel lose … [Read more...] about Corrosion
Batteries
Electrochemical cell vs Electrolytic cell Electrochemical cell Electrolytic cell It is a device which converts chemical energy into electrical energy. It is a device which converts electrical energy into chemical energy. The redox reaction is spontaneous and is responsible for the production of electrical energy. The redox reaction is non-spontaneous and … [Read more...] about Batteries
Products of Electrolysis
Products of Electrolysis During electrolysis, the reactions occurring at the electrodes are oxidation and reduction reactions. The products of electrolysis depend on the nature of material being electrolysed and the types of electrodes being used.If the electrode is inert such as gold or platinum, it does not take part in the chemical reaction and acts only as a source or sink … [Read more...] about Products of Electrolysis