The reaction in which rate depends only on one reactant concentrations, although more than one reactants are present in the reaction mixture is known as:
Correct answer: C. Pseudo first order reaction
- A. 1st order reaction
- B. 2nd order reaction
- C. Pseudo first order reaction
- D. Third order reaction
Explanation
A reaction which is not first-order reaction naturally but made first order by increasing or decreasing the concentration of one or the other reactant is known as Pseudo first order reaction. Pseudo means 'fake'.In pseudo-first order reactions, we are basically isolating a reactant by increasing the concentration of the other reactants. When the other reactants are in excess, change in their concentrations does not affect the reaction much, Therefore, now the reaction only depends on the concentration of the isolated reactant. Thus, the order of reaction becomes one.
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About Reaction Kinetics
Reaction kinetics relates reaction rate to concentration, temperature, surface area and catalysts. Questions cover rate laws, reaction order, rate constants, activation energy and the activated complex, including how a catalyst lowers the activation energy without changing the overall energy change or equilibrium position.
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