Can You Predict the Major Organic Product of This Reaction?

This is a question that often comes up in organic chemistry: can you predict the major organic product of a reaction?

The answer is, it depends. There are a number of factors that can influence the outcome of a reaction, including the reactants, the conditions, and the specific reaction mechanism.

That said, there are some general rules that can help you predict the product of a reaction. In this blog post, we’ll go over a few of them.

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In organic chemistry, the major product is the more thermodynamically stable product of a chemical reaction. The major product is often, but not necessarily, the product with the highest yield.

The notion of thermodynamic stability takes into account the energy needed to break bonds and make bonds. In general, molecules with strong bonds are more thermodynamically stable than those with weak bonds. For example, in the gas phase reaction between HCl and H2O, HCl has a stronger bond than H2O (bond energies: 432 kJ/mol for H-Cl and 463 kJ/mol for O-H). As a result, HCl is more thermodynamically stable than H2O and will be the major product of this reaction.

The major product can also be determined by considering the relative stabilities of the intermediates in the reaction. For example, in the gas phase reaction between HBr and CH3OH, two possible intermediates are H2C=O and BrCH2OH. The former is more thermodynamically stable than the latter (bond energies: 611 kJ/mol for C=O and 576 kJ/mol for C-O), so it will be the major product of this reaction.

In some cases, it may not be possible to determine the major product without doing a molecular orbital calculation. This is because there are no intermediates in these reactions and the final products have comparable stabilities. For example, in the gas phase reactions between I2 and CH4 or between Br2 and CH4, both products (CH3I or CH3Br) have similar stabilities (bond energies: 272 kJ/mol for I-I and 266 kJ/mol for B-r). As a result, these reactions could proceed by either dissipative coulombic Clara van nitrogen mechanism where one molecule of reactant abstracts a hydrogen atom from another molecule of reactant or by a third body dissociative electron transfer mechanism where iodine or bromine atom transfers an electron to methane molecule to form carbocation which then reacts with another iodine or bromine molecule to give final products

Theoretical Yield

In chemistry, the theoretical yield is the maximum amount of product a chemical reaction could create based on the amount of reactant present. The actual yield is the amount of product that is actually produced in a laboratory setting. The percent yield is a way to compare the two values and determine how efficient a reaction is.

It’s important to note that the theoretical yield is calculated based on limiting reactants. In other words, if you have more of one reactant than you need to create the desired amount of product, that extra material will not be taken into account in the theoretical yield calculation. Theoretical yield can be thought of as a “perfect” situation where everything goes according to plan and no material is wasted.

Actual yield will always be less than or equal to theoretical yield, since it’s impossible to produce more material than what was originally present. If your actual yield is less than your theoretical yield, this means that some of your reactant was not used up in the reaction or that some product was lost during purification (a process used to remove impurities from the desired product).

The percent yield is a way to express actual yield as a percentage of theoretical yield. This number can be affected by many factors, such as incomplete reactions, loss during purification, and incorrect measurements. An experienced chemist can often improve the percent yield by optimize conditions such as temperature, time, and starting materials.

Percent Yield

Percent yield is a measure of how much of the desired product is obtained from a chemical reaction. The percent yield can be calculated using the following formula:

% Yield = (Actual Yield/Theoretical Yield) x 100

For example, if you start with 30 grams of reactant A and the theoretical yield of product B is 20 grams, but you only produce 15 grams of product B, your percent yield would be:

% Yield = (15 g/20 g) x 100 = 75%

Actual Yield

The actual yield is the amount of product you actually get from a reaction. The percent yield is the ratio of actual yield to theoretical yield, multiplied by 100%. The theoretical yield is the amount of product you would get if the reaction went to completion.

Reactions don’t usually go to completion, so the actual yield is usually less than the theoretical yield. If the percent yield is low, that means there was a lot of wasted reactant.


In conclusion, it is not possible to predict the major organic product of this reaction without further information. The products that are formed depend on the specific reactants and conditions that are used.

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