[mentallychallenged]

How do you use a chemical formula to create the actual substance..if you could explain in detail or give me links i'd greatly appreciate it.

[Borek]

Please give some example of what you are trying to do.

[constant thinker]

Maybe this will help...
http://en.wikipedia.org/wiki/Chemical_Formula

I also found this...
http://en.wikipedia.org/wiki/Dictionary_of_chemical_formulas

Do what Borek said. Find example and comment on what YOU think and we'll correct if your wrong. 

[mentallychallenged]

well say i wanted to create water or H2O how would i go about getting the hydrogen and oxygen atoms to make it..im basically wondering how do i get oxygen from something or hydrogen

[constant thinker]

The simplest formula for getting water is:
2H₂ + O₂ --> 2H₂O

Your reactants (the ingredients) are on the left side and the product is on the right side. You should ask your teacher about your question. He/she could probably teacher you better face to face.

[Mitch]

Oxygen can be found in the atmosphere readily, the Hydrogen would have to be purchased somewhere, like a hardware store or something.

[mentallychallenged]

ok i have another question how would i remove it from another substance to get an amount of it and how would i contain it like say i wanted to make CH3CH2-O-CH2-CH3 how would i get all of that?

im sorry im being hard to teach but im just wondering how i could make things using chemical formulas and where they are commonly found and how to seperate them ect.

[Borek]

What you are looking for is - for all practical needs - impossible. Chemistry is about using available substances to create other substances, but you will almost never start from scratch (ie from elements) - with the exception of very simple substances. So in the real life you will never attempt to make CH₃-CH₂-O-CH₂-CH₃ from carbon, hydrogen and oxygen - you will rather start from ethanol, which can be easily bought in any amount.

Purification of reaction products is almost a science in itself. Depending on substance and impurities you may try filtration, crystallization, destillation, extraction or chromatography to name most popular methods.

[constant thinker]

CH₃-CH₂-O-CH₂-CH₃ is an ether. Ethoxyethane (diethyl ether). You may want to learn about all of the different types of reactions, oxidation states, types of compounds, valence electrons, etc.

For ethers check out
http://en.wikipedia.org/wiki/Ether
Esters
http://en.wikipedia.org/wiki/Ester
Esterification (the process of producing esters)
http://en.wikipedia.org/wiki/Esterification
General chemical formula things
http://en.wikipedia.org/wiki/Chemical_Formula
Stoichiometry
http://en.wikipedia.org/wiki/Stoichiometry

This is only scratching the surface.

Try browsing other websites too and expanding on what I gave you. I've found wikipedia to have errors sometimes.