  Home
Common Compounds
Exam Guide
FAQ
Features
Glossary
Construction Kits
Companion Notes
Simulations
Slide Index
Toolbox
Tutorial Index

FAQ
Introduction
Measurement
Matter
Atoms & ions
Compounds
Chemical change
 The mole
Gases
Energy & change
The quantum theory
Electrons in atoms
The periodic table
Chemical bonds
Solids
Liquids
Solutions
Acids & bases
Redox reactions
Reaction rates
Organic chemistry
Everyday chemistry
Inorganic chemistry
Environmental chemistry
Laboratory
History of chemistry
Miscellaneous Home FAQ The mole concept Print | Comment
 Previous Question Next Question

# How do I calculate the "expected yield" for a reaction?

I need to calculate % yield for my lab experiment. I know it equals actual yield/expected yield x100, but how do I calculate the expected yield? The equation is (CH3)3CNH2 + HC2H3O2 [(CH3)3CNH3]C2H3O2.
Tara Neely 9/10/99 Vocabulary acetic acid amine experimental yield theoretical yield limiting reagent percent yield The expected or theoretical yield is the amount of product obtained if the limiting reagent reacts completely.
1. Write the balanced equation for the reaction. You've already done that. (For more about balancing equations, see How can I tell if an equation is balanced properly? and Ten tips for balancing equations).
2. Identify the limiting reagent. In this case, every mole of (CH3)3CNH2 needs a mole of HC2H3O2, so whichever reactant is present in the smaller molar amount will limit the amount of product obtained.

With more complex reactions, you can identify the limiting reagent by calculating the amount of product produced if each reactant in turn is consumed completely. (For an example, see How can amount of product be predicted when the amounts of two reactants are known?)

3. Predict the amount of product obtained if the limiting reagent is consumed completely. For example, if 0.100 mol of the amine (CH3)3CNH2 reacted with excess acetic acid HC2H3O2, the expected yield of the product [(CH3)3CNH3]C2H3O2 is
 0.100 mol amine ( 1 mole product1 mol amine ) ( 133 g product1 mole product ) = 13.3 g product

Author: Fred Senese senese@antoine.frostburg.edu

General Chemistry Online! How do I calculate the "expected yield" for a reaction?