Question

For a reaction, the initial concentrations and corresponding rates are given. Which method is used to calculate the rate constant?

• A. Integration method
• B. Differential method
• C. Initial rate method
• D. Half-life method

Hint:

If you see a table with "Experiment 1, 2, 3" showing different starting Molarities and Rates, you are looking at the Initial Rate Method. You can find the order \(n\) by using the ratio: \(\frac{Rate_1}{Rate_2} = \left(\frac{[A]_1}{[A]_2}\right)^n\).

Answer 1

The Correct Option is C

Step 1: Understanding the Concept
Different experimental methods exist to determine the order of a reaction and the rate constant. The choice depends on the type of data provided.

Step 2: Detailed Explanation
1. Initial Rate Method: This method involves running the reaction multiple times with different starting (initial) concentrations of reactants and measuring the initial rate for each. By comparing how the rate changes as concentration changes, the order and then the rate constant (\(k\)) can be determined. 2. Integration Method: Used when concentration data is given as a function of time (\(t\)) for a single run. 3. Half-life Method: Used when the time taken for concentration to reduce by half is measured at different initial concentrations. 4. Differential Method: Relates the rate of reaction to the concentration at any point in time during the reaction.

Step 3: Final Answer
The method used when initial concentrations and corresponding rates are given is the Initial rate method.