[DesertRose]

hi, when you are asked to find the given chemical formulae of certain compound, (i know the procedure for finding it), but is it possible to just exchange the charges and place them at the bottom of the element instead??
eg; write the chemical formulae of CuO.
     if you exchange the charges and place them at the bottom of each individual element, you will get Cu2O2.
is that possible?
any help would be kindly appreciated!!
thank you!

[Schrödinger]

write the chemical formulae of CuO.

Chemical formula of CuO is CuO!!

[DesertRose]

Cu(2)O
how is it CuO???
help please???

[icyhead]

theyre 2 different compounds, I think you need to read up on oxidation states i cant remember much but Copper can have an oxidation state of +1 or +2.

[DesertRose]

yes, that is correct. the state i'm refering to is +1

[Schrödinger]

If Copper is in +1 state, then it should be clear why the formula is Cu2_O

When Copper's oxidation state is +2, then the formula would be CuO, not Cu₂O₂. Generally, common factors are canceled.
For instance, you don't write C₂O₄ do you? You just write CO₂

[DesertRose]

ok thanks!

[skyjumper]

In high school I was taught to merely use the cations charge as the anions subscript, and reverse. For example, CaCl₂ could be found by saying that Ca is Ca²⁺ and Cl^1- We would then "criss cross" (That's what she called it... The "Criss cross" method, oh public high school, you) To get Ca₁Cl₂ and as we all know, 1 in chem is understood so, we end up with just CaCl₂

You then reduce the subscripts by there GCF so Ca₂O₂ may be reduced by the GCF of 2, to simply CaO.
Nothing new there, just hoping to help explain it.

[Schrödinger]

For example, CaCl2 could be found by saying that Ca is Ca2+  and Cl1- We would then "criss cross" (That's what she called it... The "Criss cross" method, oh public high school, you) To get Ca2Cl1  and as we all know, 1 in chem is understood so, we end up with just Ca2Cl

CaCl₂, not Ca₂Cl

[skyjumper]

Such a stupid mistake :p, I need sleep

[DesertRose]

Thanks!! 

[vmelkon]

hi, when you are asked to find the given chemical formulae of certain compound, (i know the procedure for finding it), but is it possible to just exchange the charges and place them at the bottom of the element instead??
eg; write the chemical formulae of CuO.
     if you exchange the charges and place them at the bottom of each individual element, you will get Cu2O2.
is that possible?
any help would be kindly appreciated!!
thank you!

Cu2O2 is called copper(I) peroxide because it would have the O2 -2 ion.
In this ion, you would have a oxygen bonded to an oxygen O-O.
To each O, you can have a Cu +1 bonded.
It would look like Cu - O - O - Cu very much like the case for other peroxides like H2O2, Na2O2, CaO2, MgO2.
I don't know if Cu2O2 has been produced.

It sounds more like you are talking about CuO, copper(II) oxide. In this, you have 1 Cu +2 and one O -2

[DesertRose]

ok thanks!!!!