Finding the Empirical Formula from a Molecular Formula

• Author: Dr. David Yaron
• Subject: Science and Technology
• Institution Name: Carnegie Mellon University
• Collection: The ChemCollective
• Grade Level: Post-secondary

• Abstract: Elemental analysis is a useful qualitative analysis technique since it allows us to check if a sample is consistent with a given molecular formula. For instance, suppose we believe our sample is benzene (C6H6). We can compare the following:The empirical formula (CH) obtained from the molecular formula of benzene (C6H6); The empirical formula obtained from a elemental analysis of the sample. If the two empirical formulae do not agree, then the sample is not benzene. If the formulae agree, then our sample may be benzene. (Remember that more than one molecule can have the sample empirical formula. For instance, both benzene (C6H6) and acetylene (C2H2) have the empirical formula CH, so a sample whose elemental analysis yields CH as an empirical formula could be benzene, acetylene, or some other molecule with a 1:1 ratio between C and H.)

• Course Type: Learning Module
• Languages: English
• Material Types: Homework and Assignments
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