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kazemagic

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Why is SO3 called sodium trioxide not sodium oxide. Why is (Al2)(O3) called aluminum oxide but not aluminum trioxide
 

theind1996

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Why is SO3 called sodium trioxide not sodium oxide. Why is (Al2)(O3) called aluminum oxide but not aluminum trioxide
It's just the way it is for ionic compounds, you only add tri-, di- etc. for covalent compounds.

(There's no logic behind it, just memorise the naming system lol.)
 

Aysce

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Prefixes such as tri are only used for covalent compounds. To recognise a covalent compounds, we know that they are formed between only non-metals e.g. SO3. Lets take a look at (AL2)O3. You can tell that AL is a metal and O is a non-metal, in which this is an ionic compound. Since it is ionic, prefixes are not required.

EDIT: Sadly beaten by this animal kient.
 

kazemagic

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O i c thx guise
I thought the di tri stuff are all part of ionic compounds lol... If covalent bond is only between non-metals and SO3 is a covalent bond, isnt sodium a metal O_O
edit: nvm
 
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deswa

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O i c thx guise
I thought the di tri stuff are all part of ionic compounds lol... If covalent bond is only between non-metals and SO3 is a covalent bond, isnt sodium a metal O_O
Yeah sodium is a metal...
 

theind1996

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I thought the di tri stuff are all part of ionic compounds lol... If covalent bond is only between non-metals and SO3 is a covalent bond, isnt sodium a metal O_O
s isn't sodium hahah, it's sulfur (i'm a fucking idiot).
 

someth1ng

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Yeah, it's two different naming schemes. Here are examples:

SO2 and SO3 are sulfur dioxide and sulfur trioxide.
CuO and Cu2O are copper(II) oxide (or cupric oxide) and copper(I) oxide (or dicopper oxide [sometimes] or cuprous oxide).

So, as you can see, there's different naming schemes for each one - for ionic ones, you tend to metal(valency) oxide but for covalent ones, you tend to have non-metal (prefix denoting # of atoms)oxide.

Realistically, people WILL understand but the metal(valency) oxide and non-metal (prefix)oxide are preferred and usually the correct and most accepted ways of naming.
 

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