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In the following questions a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion : The enthalpy of reaction remains constant in the presence of a catalyst.
Reason : A catalyst participating in the reaction, forms a different activated complex and lowers down the activation energy but the difference in energy of reactant and product remains the same.
  • a)
    Both assertion and reason are true and the reason is the correct explanation of assertion.
  • b)
    Both assertion and reason are true but the reason is not the correct explanation of assertion.
  • c)
    Assertion is true but reason is false.
  • d)
    Assertion is false but reason is true.
Correct answer is option 'A'. Can you explain this answer?
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In the following questions a statement of assertion followed by a sta...
It is believed that the catalyst provides an alternate pathway or reaction mechanism by reducing the activation energy between reactants and products and hence lowering the potential energy barrier but the enthalpy of reaction remains constant.
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In the following questions a statement of assertion followed by a sta...
Assertion: The enthalpy of reaction remains constant in the presence of a catalyst.
Reason: A catalyst participating in the reaction forms a different activated complex and lowers down the activation energy, but the difference in energy of reactant and product remains the same.

Explanation:
A catalyst is a substance that increases the rate of a chemical reaction by providing an alternative reaction pathway with a lower activation energy. It does not undergo any permanent change in its own composition during the reaction.

The given assertion states that the enthalpy of the reaction remains constant in the presence of a catalyst. Enthalpy is a measure of the heat energy change during a chemical reaction. According to the reason provided, a catalyst forms a different activated complex and lowers down the activation energy.

Let's analyze the given options:

a) Both assertion and reason are true and the reason is the correct explanation of the assertion.
b) Both assertion and reason are true but the reason is not the correct explanation of the assertion.
c) Assertion is true but reason is false.
d) Assertion is false but reason is true.

To determine the correct answer, let's examine the explanation further.

1. The Role of a Catalyst:
- A catalyst provides an alternative reaction pathway with a lower activation energy.
- It does not affect the energy difference between the reactants and products.
- A catalyst lowers the activation energy barrier but does not change the overall energy change of the reaction.
- It speeds up the rate of the reaction by making it easier for the reactants to reach the activated complex and form the products.

2. Enthalpy of Reaction:
- The enthalpy of reaction is the difference in energy between the reactants and products.
- It represents the heat energy change during a chemical reaction.
- The enthalpy change remains the same whether a reaction occurs with or without a catalyst.

Therefore, the correct answer is option 'A' - Both the assertion and reason are true, and the reason is the correct explanation of the assertion.

In conclusion, the presence of a catalyst does not affect the enthalpy of reaction because it only provides an alternative reaction pathway with a lower activation energy. The catalyst does not change the overall energy change of the reaction, and thus, the enthalpy remains constant.
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In the following questions a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.Assertion : The enthalpy of reaction remains constant in the presence of a catalyst.Reason : A catalyst participating in the reaction, forms a different activated complex and lowers down the activation energy but the difference in energy of reactant and product remains the same.a)Both assertion and reason are true and the reason is the correct explanation of assertion.b)Both assertion and reason are true but the reason is not the correct explanation of assertion.c)Assertion is true but reason is false.d)Assertion is false but reason is true.Correct answer is option 'A'. Can you explain this answer?
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