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Non Life Sciences => Chemistry => Topic started by: mogsmar5 on 09/01/2010 19:04:38

Title: How do we know the valencies of covalently bonded compounds?
Post by: mogsmar5 on 09/01/2010 19:04:38

Hi,

As part of the stuff I got given at the start of my AS Chemistry course I was given a table of the charges of different ions, both single-element and multi-atom (my terminology, unsure on the actual names). Obviously knowing this table is essential to correctly writing the formulae of ionic compounds.

Now, is there an equivalent for covalently bonded compounds? If there is, is it essentially finding the valencies of the non-metals concerned and using those?

Thanks,
George

Title: How do we know the valencies of covalently bonded compounds?
Post by: Spannerman on 24/02/2010 18:21:16

Hey George, I have just started As chemistry.

Surely one can assume that most of the covalently bound compounds follow the octet rule and therefore would have eight valence electrons. The only exceptions to this that I know of are the Phosphorus compounds that can have up to 10 valence.

In covalent bonding you do need to know the number of valence electrons in order to right out a balanced formulae. The number of valence can be easily obtained from the group the element is in. E.g. Group 4 - 4 Valence
     Group 2 - 2 Valence

Title: How do we know the valencies of covalently bonded compounds?
Post by: bosede on 04/03/2010 16:47:45

Hi, george
 Most of the covalently bound compounds follow the octet rule and therefore would have eight valence electrons. The only exceptions to this that I know is Phosphorus compounds that can have up to 10 valence.

Title: How do we know the valencies of covalently bonded compounds?
Post by: Spannerman on 04/03/2010 19:38:13

Repeating information, there bosede.