Question #ce7a4

1 Answer
Stefan V.
Apr 30, 2016

#"C"_9"H"_8"O"_4#

Explanation:

As it turns out, the problem already provides you with the molecular formula and the empirical formula of aspirin, or acetylsalicyclic acid, #"C"_9"H"_8"O"_4#.

http://www.123rf.com/photo_18083157_structural-model-of-aspirin-molecule.html

A compound's molecular formula tells you the exact number of atoms of each constituent element present in one molecule of this compound. In your case, one molecule of aspirin contains

  • nine atoms of carbon, shown here in black
  • eight atoms of hydrogen, shown here in light gray
  • four atoms of oxygen, shown here in red

This is why the compound's molecular formula is #"C"_9"H"_8"O"_4#.

Now, the empirical formula tells you the smallest whole number ratio that exists between a compound's constituent elements.

In this case, a #9:8:4# ratio between carbon, hydrogen, and oxygen is already the smallest than can be expressed using whole numbers, which means that #"C"_9"H"_8"O"_4# is also the empirical formula of aspirin.

#color(green)(|bar(ul(color(white)(a/a)color(black)("C"_9"H"_8"O"_4)color(white)(a/a)|))) -># empirical and molecular formula

Related questions
See all questions in Empirical and Molecular Formulas
Impact of this question
10034 views around the world
You can reuse this answer
Creative Commons License