Ethyl acetate is one of the most widely used organic solvents in coatings, adhesives, printing inks and pharmaceutical processing. Understanding its molecular weight, formula weight and molar mass is essential for stoichiometric calculations, formulation work and quality control. This article explains what each term means, how the values are derived, and why the three figures are numerically identical for ethyl acetate.
Ethyl Acetate Formula and Molecular Weight
Ethyl acetate has the chemical formula C4H8O2 and a molecular weight of approximately 88.11. It is an ester formed from ethanol and acetic acid, and is also known as ethyl ethanoate. The following table summarizes its basic identity data.
| Property | Value |
|---|---|
| Chemical Name | Ethyl Acetate |
| Chemical Formula | C4H8O2 |
| CAS Number | 141-78-6 |
| Molecular Weight | 88.11 |
| Formula Weight | 88.11 |
| Molar Mass | 88.11 g/mol |
What Is the Molecular Weight of Ethyl Acetate?
The molecular weight of ethyl acetate is approximately 88.11. This relative value expresses the mass of a single molecule compared with the unified atomic mass unit, and therefore carries no physical unit of its own. It is calculated by adding the atomic weights of every atom in the molecule: 4 carbon atoms, 8 hydrogen atoms and 2 oxygen atoms. For technical calculations, this figure is used to compare ethyl acetate with other solvents and to determine stoichiometric ratios in chemical reactions.
What Is the Formula Weight of Ethyl Acetate?
The formula weight of ethyl acetate is approximately 88.11, obtained by summing the atomic weights of all atoms shown in the chemical formula:
4 carbon atoms, about 12.01 each, total 48.04
8 hydrogen atoms, about 1.008 each, total 8.06
2 oxygen atoms, about 16.00 each, total 32.00
Overall total, approximately 88.11
For a molecular compound such as ethyl acetate, the formula weight and the molecular weight converge on the same number; the difference lies in what each term technically refers to.
What Is the Molar Mass of Ethyl Acetate?
The molar mass of ethyl acetate is approximately 88.11 g/mol, which adds a physical unit to the same underlying number. In practice, 1 mole of ethyl acetate weighs about 88.11 grams. This is the figure used whenever a real quantity such as kilograms, drums or tank volumes must be converted to or from moles for a chemical calculation.
Molecular Weight vs. Formula Weight vs. Molar Mass
These three values are numerically identical for ethyl acetate but describe different quantities. The table below clarifies the distinction.
| Term | Meaning | Unit |
|---|---|---|
| Molecular Weight | Mass of one molecule relative to the atomic mass unit | None, dimensionless |
| Formula Weight | Sum of atomic weights of all atoms in the formula unit | None, dimensionless |
| Molar Mass | Mass of one mole of the substance | g/mol |
In analytical work and process design, reporting the value as 88.11 g/mol is recommended because it carries the unit needed for mole conversions.
How Is Ethyl Acetate Molar Mass Used?
Ethyl acetate molar mass supports everyday industrial tasks such as preparing solvent mixtures at a given mole fraction, calculating vapor concentrations in ventilation design, and scaling laboratory recipes to production batches. It also appears in safety calculations, for example when estimating the amount of solvent evaporated from an open process.
Frequently Asked Questions
What is the molecular weight of ethyl acetate?
The molecular weight of ethyl acetate C4H8O2 is approximately 88.11, a dimensionless value calculated from 4 carbon, 8 hydrogen and 2 oxygen atoms.
What is the difference between molecular weight and molar mass?
Molecular weight is a dimensionless relative value, while molar mass is the same numerical quantity expressed with the unit g/mol. For ethyl acetate both equal 88.11.
What is the CAS number of ethyl acetate?
The CAS registry number of ethyl acetate is 141-78-6.
Why is the molar mass of ethyl acetate important in formulation?
It allows conversion between mass and moles, which is necessary for stoichiometric calculations, concentration adjustments and solvent replacement decisions.
Is ethyl acetate the same as ethyl ethanoate?
Yes, ethyl ethanoate is the IUPAC-preferred name for the same compound, with the formula C4H8O2 and CAS number 141-78-6.