The following mechanism has been proposed for the gasphasereaction of chloroform 1CHCl32 and chlorine:Step 1: Cl21g2 Δ k1 k - 1 2 Cl1g2 1fast2Step 2: Cl1g2 + CHCl31g2 ¡k2 HCl1g2 + CCl31g2 1slow2Step 3: Cl1g2 + CCl31g2 ¡k3 CCl4 1fast2(a) What is the overall reaction?

Verified step by step guidance

1. Identify the reactants and products in each step of the mechanism.
2. Write down the reactants and products for each step: Step 1: Cl2(g) -> 2 Cl(g), Step 2: Cl(g) + CHCl3(g) -> HCl(g) + CCl3(g), Step 3: Cl(g) + CCl3(g) -> CCl4(g).
3. Add up all the reactants and products from each step to find the overall reaction.
4. Cancel out any intermediates that appear on both sides of the equation. In this case, Cl(g) and CCl3(g) are intermediates.
5. Write the simplified overall reaction after canceling intermediates: Cl2(g) + CHCl3(g) -> HCl(g) + CCl4(g).

Key Concepts

Reaction Mechanism

A reaction mechanism is a step-by-step description of the pathway through which reactants are converted into products. It outlines individual elementary steps, including the sequence of bond-breaking and bond-forming events. Understanding the mechanism helps in predicting the rate of reaction and the overall stoichiometry of the process.

Rate-Determining Step

The rate-determining step (RDS) is the slowest step in a reaction mechanism that controls the overall reaction rate. In the provided mechanism, the second step is identified as slow, indicating that it is the RDS. Recognizing the RDS is crucial for understanding how changes in conditions can affect the reaction rate.

Overall Reaction Equation

The overall reaction equation summarizes the net change from reactants to products, combining all elementary steps while canceling out intermediates. To derive the overall reaction from the mechanism, one must add the individual steps and eliminate any species that appear on both sides of the equation, leading to a balanced representation of the chemical transformation.