Formula of Lactic acid is given as C3H6O3, can't this be divided by the common factor3, and written as CH2O?

  • 2
    $\begingroup$ This was supposed to be a molecular formula. You don't divide molecules. $\endgroup$ – Ivan Neretin Aug 31 '18 at 6:25
  • 4
    $\begingroup$ FWIW, CH2O is the correct "empirical formula" for lactic acid, as you would calculate from elemental analysis. $\endgroup$ – iad22agp Aug 31 '18 at 9:54
  • $\begingroup$ Basically, you can simplify or "divide" a molecular formula only if it really makes sense. $\endgroup$ – SteffX Aug 31 '18 at 15:31
  • $\begingroup$ Basically, a given molecule has a unique (molecular) formula. However, some molecules have a tendency to associate to form bigger molecules. Only in that case can you simplify or "divide" a molecular formula. For example, elemental sulfur (S) is usually found in nature as S8 and then you can consider its true formula is S. Also P4S10 is a dimer of P2O5; you have P4S10 in your flask but you can consider P2O5 in your calculations. $\endgroup$ – SteffX Aug 31 '18 at 15:37

You have initially tagged your question "structural formula", however $\ce{C3H6O3}$ is somewhat ambigous in this respect, and besides lactic acid can represent its isomer 3-hydroxypropionic acid, methoxyacetic acid, and almost completely different compounds like dihydroxyacetone, dimethyl carbonate, glyceraldehyde or trioxanes, not speaking of the second one $\ce{CH2O}$ (formaldehyde or ethylene oxide). Well, these are not structural formulas at all.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.