Grignard Reaction Stoichiometry Calculator

Summary

The Grignard Reaction Stoichiometry Calculator determines the moles of each reactant from the amounts and molecular weights you enter, identifies the limiting reagent, calculates the theoretical yield of product, and shows how much excess reagent remains. It handles the standard 1:1 Grignard reagent-to-electrophile ratio and supports custom stoichiometric coefficients for non-standard reactions.

How it works

1. Enter the mass and molecular weight of your Grignard reagent (RMgX).
2. Enter the mass and molecular weight of the electrophile (e.g., ketone, aldehyde, ester).
3. Optionally enter the molecular weight of the expected product.
4. Enter stoichiometric coefficients if your reaction is not 1:1.
5. Click Calculate to see moles, limiting reagent, excess amount, and theoretical yield.

Use cases

• Plan a Grignard addition to a ketone or aldehyde before running the reaction.
• Determine how many equivalents of Grignard reagent you have relative to the electrophile.
• Calculate theoretical product mass for nucleophilic addition reactions.
• Optimize reagent ratios to minimize waste of expensive Grignard reagents.
• Verify stoichiometry in undergraduate and graduate organic chemistry labs.
• Scale Grignard reactions up from milligram to gram scale while keeping ratios correct.

Frequently Asked Questions