Worked example

Theor 50.0 g, actual 42.0 g →84.0%.

Percent Yield

Compare actual to theoretical product mass.

Equation

$\%_{yield}=\frac{m_{actual}}{m_{theoretical}}\times100$

Inline: $%{yield}=\frac{m{actual}}{m_{theoretical}}\times100$$

Variables

Symbol	Quantity	Unit	Notes
$$	percent yield	%	—
$m_actual$	actual mass	g	—
$m_theor$	theoretical mass	g	—

Conditions and limitations

Same product, same reaction.

Rearrangements

$m_{theor}=m_{actual}/\%×100$

Dimensional check: %

Worked example

Theor 50.0 g, actual 42.0 g →84.0%.

Steps: write equation → substitute with units → check dimensional consistency → report with correct significant figures.

Common errors

• Exceeding 100% without recognizing error
• Using moles vs mass inconsistently

Related resources

• mole-stoichiometry topic
• Calculators — linked only when a real calculator implements this formula.
• Constants — sourced constants with version when values are required.

Sources

• NIST Physical Constants 2022 — CODATA.

Reviewed 2026-08-21 by Editorial Team; due 2027-08-21.