If a reaction is first order with respect to a reactant then the rate will be ---- if the concentration of the reactant is doubled.
Correct answer: A. Doubled
- A. Doubled
- B. halved
- C. One fourth
- D. quadrupled
Explanation
When a reaction is said to be first order with respect to a reactant, it means that the rate of the reaction is directly proportional to the concentration of that reactant raised to the power of one.Mathematically, if we have a first-order reaction with respect to reactant A, the rate equation would be expressed as:rate = k[A]^1Where [A] represents the concentration of reactant A, and k is the rate constantNow, if the concentration of reactant A is doubled, the new concentration would be 2[A]. Substituting this into the rate equation:new rate = k[2A]^1Since 2A is twice the concentration of A, we can simplify the equation as follows:new rate = 2k[A]^1As we can see, the new rate is twice the original rate. Therefore, if the concentration of the reactant is doubled, the rate will also be doubled. This is why option A is correct.
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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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