More MCH Science Software

College Science Software BundleCollege Science Bundle: The three college level courses - General Chemistry, General Physics (calculus) and Organic chemistry, bundled together in one package.College Science Software Bundle


High School Science Bundle: The two high school level courses- Introductory Chemistry and General Physics (non- calculus), bundled together into one package. This bundle is very popular with High School and Home School students.Chemistry and Physics Software for High School and Home School

Chemical Reactions; What? How much? How fast?

Standard Daniell Cell

Click to enlarge

When dealing with chemical reactants, three important questions are usually asked.

(1)    What product(s) can be made,

(2)    How much can be made and

(3)    How fast can it be made. 

What?

The first question relies on knowledge about the characteristics of each reactant and being able to “predict” how they will react together. This power of prediction spans many areas of chemistry, including: inorganic, electrochemical, organic and bioorganic/biological.

In general chemistry inorganic reactions are predicted based on the formation of a solid, gas, weak or non-electrolyte using metathesis or double replacement reactions. Memorization of common gases and the solubility rules aid students in their predictions.

Electrochemical reactions, discussed in chapter 8 of the Physical Chemistry textbook, rely on the use of oxidation and reduction potentials in redox reactions.  Reference tables can be used to determine which reactions will proceed and are closely linked with thermochemical constants.

Organic reactions generally deal with carbon and other non-metals and require a more in depth knowledge of oxidation and reduction, the bonding theories:  valence bond theory and molecular orbital theory and the molecules environment.

Bioorganic/Biological reactions are similar but generally deal with very large molecules so the focus is on one specific reactive site.

How much?

The quantitative question, how much can be made, is first answered by understanding balanced stoichiometry and conversions between different units.  Unfortunately, the question is not usually that simple.

An understanding of chemical equilibrium (covered in chapters 4 and 6 – Thermodynamics module), the balance or ratio of reactant to product, is needed before any calculation can be made.  It becomes even more complex because any disturbance changes that balance.

How fast?

How fast products can be made, kinetics, is a very complex question that often deals with a more detailed look at what is actually occurring inside the reaction and is the focus of both chapters 9 and 10 (Kinetics module).

Reactions are viewed as a series of steps that describe what is actually occurring that lead to the overall product.  These steps do not always resemble the original equation.  Each step requires a certain amount of energy, activation energy, and has a specific speed or rate.

How fast the overall reaction proceeds is ultimately determined by the slowest or rate determining step.

While basic chemical knowledge from general chemistry is required, this textbook covers each of these questions in depth.

Written by: jollshar

Sharlene Jolley has authored 20 more articles.

I received my graduate degree in organic chemistry from Kansas State University and have been teaching undergraduate chemistry courses for over 15 years. I strongly believe that you are never too old or young to learn and appreciate science and have had students ranging in ages from 5 to 65. Along with my college classes, I regularly teach science in K-12 classes and for special interest groups.

Leave a Reply

Your email address will not be published. Required fields are marked *

Try our bestselling undergraduate Physical Chemistry courseware

Thermodynamics Module - Physical Chemistry
Thermodynamics module
Chapters 1 to 6 of Physical Chemistry - Laidler, Meiser, Sanctuary


Includes multimedia that opens on relevant pages and allows the student to visualize many of the concepts by varying parameters and plotting different graphs. Things students often have difficulty with, such as isothermal, isobaric, isochoric and adiabatic process, are clearly visualized.

Get it from: Thermodynamics Module - Physical Chemistry



Physical Chemistry - Laidler, Meiser, Sanctuary
Physical Chemistry textbook
by Laidler, Meiser, Sanctuary


This popular Physical Chemistry text book is now available in electronic format. We have preserved much of the material of the former hard copy editions, making changes to improve understanding of the concepts in addition to including some of the recent discoveries in physical chemistry. Many chapters have new sections and the coverage of several chapters has been greatly expanded.

Get it from: Physical Chemistry - Laidler, Meiser, Sanctuary

PChemistry Tips by Email

Don't miss out on Physical Chemistry tips & special offers sent via email

* indicates required


Categories
MCH on Twitter