How are reactions classified according to their rates? Give one exampl

1.	How are reactions classified according to their rates? Give one example of each.
Answer» According to the rates of the reactions, they can be classified as : (1) Fast reactions, (2) Very slow reactions, (3) Moderately slow reactions. (1) Fitst actions : In this, reactants react almost instantaneously, e.g., neutralisation reaction between H⁺ and OH^-, forming water. H+(xa) + OH-(aq) → H₂O_0D (2) Very slow reactions : In this, the reactants react extremely slow, so that there is no appreciable change in the concentrations of the reactants over a long period of time. E.g., reaction of silica with mineral acids, rusting of iron, etc. (3) Moderately slow reactions : In this, the reactants react moderately slow with a measurable velocity, e.g., the hydrolysis of the esters. CH₃COOC₂H₅ + H₂O \(\overset{H^+}\longrightarrow\) CH₃COOH + C₂H₅OH

How are reactions classified according to their rates? Give one example of each.

Answer»

According to the rates of the reactions, they can be classified as :

(1) Fast reactions,

(2) Very slow reactions,

(3) Moderately slow reactions.

(1) Fitst actions : In this, reactants react almost instantaneously, e.g., neutralisation reaction between H⁺ and OH^-, forming water.

H+(xa) + OH-(aq) → H₂O_0D

(2) Very slow reactions : In this, the reactants react extremely slow, so that there is no appreciable change in the concentrations of the reactants over a long period of time.

E.g., reaction of silica with mineral acids, rusting of iron, etc.

(3) Moderately slow reactions : In this, the reactants react moderately slow with a measurable velocity,

e.g., the hydrolysis of the esters.

CH₃COOC₂H₅ + H₂O \(\overset{H^+}\longrightarrow\) CH₃COOH + C₂H₅OH

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