Comments on: Can Anyone Give Me An Easy Way To Figuring Out The Chemical Formulas To Compounds?

By: Doc_Cain

Doc_Cain — Sat, 05 Dec 2009 02:25:11 +0000

It’s easy easy when u have ur periodic table on hand. For example with magnesium oxide (obviously u should know the symbols if not there’s only one thing to do… learn them)
So we have: Mg and O,
Mg is in the 2nd column and so has a charge of +2
O is in the 2nd last column and so has a charge of -2
So both have the same chare so just combine them: MgO
If we look at water: H is in 1st column so has a +1 charge
O is in 2nd last so has a charge of 2-
so u need 2 H for every 1 O (because the charges need to balance.
so: H2O (the 2 should be a subscript)
all the elements between the 2nd column and the 3rd last column can have varying charges(except for silver, Ag which has a +1 charge), like iron, they normaly tell u what the charge is though like Fe(III) is iron with a 3+ charge, etc.
(Rule of thum: the element with the lower amount of charge gets the higher number after it, in the resulting equation) for an example take a look at water again.
Of course the best way to become quick and efficient in determining the resulting chemical formulas is to practice, practice, practive…
Good Luck

By: perox1so

perox1so — Fri, 04 Dec 2009 19:36:05 +0000

metal in front non metal in behind.
Na Cl = NaCl
KF
Mg2O2 the 2 cancel out
MgO
G1 charge 1
G2 charge2 and so on g7 charge 1 g6 charge 2 g 5 charge 3 g 4 charge 4 g 3 charge 3g8 charge none

By: Ruphert J

Ruphert J — Fri, 04 Dec 2009 14:29:41 +0000

do you know how to see what the charge is, look on the periodic table, column 1a all have +1 charge, column 2a has +2 charge, column 3a have +3 charge. Now start from the right side of the table, all the 8a have no charge, the 7a have -1 charge, the 6a have -2 charge, the 5a have -3 charge and the 4a have -4 charge.
Now to get the chemical formula you just make them neutral, Potassium is in 1a so it has a +1 charge Fluorine is in 7a so it has a -1 charge, so they go together at a 1:1 ratio. KFl
Mg is 2+ and Oxygen is 2- so they go together and make a neutral product as well MgO. Now say you got Potassium Oxide. Potassium has 1+ so you need two of those to make the product neutral because Oxygen is 2-. so K2O The 2 should be a subscript of course.