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 Type:

Homework and Assignments

Media Format:

Text/HTML, Downloadable docs, Video

Conditions of Use:

Custom Permissions
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