Chemlab: Chemistry 6


Chemical Kinetics 1

Overview

Getting Started

Techniques

Procedure

FAQ

Full Lab Manual

Introduction & Goals

Chemistry & Background

Key Questions

Prelab Problems

Safety

Procedure

In Your Write-up

Experiments Index

ChemLab Home


Applets

Kinetics Plot
This applet allows you to enter kinetic data and plot the absorbance vs. time, the natural log of absorbance vs. time, or the inverse of absorbance vs. time. This will allow you to quickly evaluate the reaction order since these are the expected linear plots for zero, first, and second order reactions, respectively.

Linear Least Squares
This applet allows you to enter any linear data and determine the best-fit slope of the line. You can use this applet to determine the slope of your lines, once you have your kinetics data in a linear form.

Technique Links

Spectrometer

Pipet

Buret

Goals
In this two-week experiment you will measure the rates of chemical reactions. By observing the progress of a reaction over time, you will determine the rate law, test a possible mechanism, and determine the temperature dependence of the reaction rate constant. In week 1, you will determine the rate law and postulate a rate limiting step for the reaction. In week 2, you will measure the rate constant at different temperatures, to determine the reaction's activation energy.

Key Questions
1. How do you determine the rate law of a reaction?

2. What is the reaction order with respect to each reactant and how can you distinguish between a zero, first, or second order reaction?

3. What is a rate limiting step of a reaction and how does it effect the rate law observed?
Time-lapse view of this week's reaction

Here is a slide show (which loops endlessly) of this week's reaction. As the reaction procedes, the color of one reactant fades, leaving a colorless solution. You will observe the progress of the reaction over time by measuring the absorbance of this colored reactant.

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