Sciencemadness Discussion Board

How to predict a substance properties?

Blind Angel - 1-12-2002 at 16:22

How can we predict substance properties only with is chemical formula?
Anyone has a link where i can find info or just (briefly or not) explain me how

Microtek - 2-12-2002 at 03:56

It's not something that is easily done. Some properties can be predicted by knowing the structure of a compound, for instance whether it's a covalent of an ionic compound or if it is water soluble or not.
However, predicting the properties of matter is generally something that takes a lot of experience, a lot of knowledge and a little intuition. I don't know of any shortcuts ( except for expensive software that predicts a very narrow set of properties for a very narrow spectrum of compounds ).

BlackDragon2712 - 25-11-2013 at 15:57

http://www.chemaxon.com/marvin/sketch/index.jsp
Here you can predict some of the properties, not all but is still a very useful tool if you ask me.
Now, if you have access to make a FTIR analysis on the other hand...

[Edited on 06/11/2013 by BlackDragon2712]

AJKOER - 25-11-2013 at 17:49

OK, knowing the observed associated properties of 'family' members can give one some expectations that are, at times, good.

For example, taking the family as the halogens, knowing the disproportionation properties of HClO, does give good clues as to the behavior of HBrO and HIO. The oxides of Chlorine (Cl2O, ClO2,...) gives clues as to possible oxides of Bromine and Iodineand their properties.


bfesser - 25-11-2013 at 18:59

Understanding <a href="http://en.wikipedia.org/wiki/Periodic_trends" target="_blank">periodic trends</a> <img src="../scipics/_wiki.png" />, and having knowledge of the properties of common ions and <a href="http://en.wikipedia.org/wiki/Functional_group" target="_blank">functional groups</a> <img src="../scipics/_wiki.png" /> is helpful.

UnintentionalChaos - 25-11-2013 at 19:06

1) Holy necro thread, Batman! 11 years. I think that may be a record.

2) You could rub it into your gums and see what happens.

[Edited on 11-26-13 by UnintentionalChaos]

BlackDragon2712 - 25-11-2013 at 19:27

Quote: Originally posted by UnintentionalChaos  
1) Holy necro thread, Batman! 11 years. I think that may be a record.


wait?! the thread is 11 years old? wow for how long this page has existed?!!! sry for not realizing that, but my sciencemadness hour thing just got messy and I have no idea how to fix it :/ hahahaha

AJKOER - 26-11-2013 at 06:14

OK, it only took 11 years to answer his homework question (must be a record).:)

woelen - 26-11-2013 at 07:50

This may be an old question, but it is an interesting one. If we have information about the structure and not only a net formula, then more can be done. Using (fantastically complicated) calculations, using quantum mechanics, it is possible to compute quite a few properties for small atoms and ions. I can imagine that things like stability, macroscopically observed color in the solid state, solution or gas phase, and maybe even the reactions with other simple compounds can be computed. Even for very small molecules or ions, however, the computations are huge and a very fast computer is needed for accurate results.

blogfast25 - 29-11-2013 at 10:01

Much can be gleaned from the nature of the chemical bonds that hold a substance together. The mystery of chemical bonding was one of the greatest riddles of science and one that was ultimately solved by quantum mechanics.

Whether the atoms in a pure substance are bound together by ionic bonds, purely covalent covalent, anything in between or a combination thereof determines much of the substance's physical and chemical properties.