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Chemistry

How do I know if a structure is simple covalent or simple molecular lattice ? Or in general how do I state what structure a molecule has ?
Original post by Alevelhelp.1
How do I know if a structure is simple covalent or simple molecular lattice ? Or in general how do I state what structure a molecule has ?

Often you can tell from non metal vs metal combination. Also looking at physical properties if you are given them, like the boiling point?
Do you have a specific example?
Original post by booklover1313
Often you can tell from non metal vs metal combination. Also looking at physical properties if you are given them, like the boiling point?
Do you have a specific example?

Sodium chloride.
And s8.
And Sodium Nitrate.
Original post by Alevelhelp.1
Sodium chloride.
And s8.
And Sodium Nitrate.

You know that sodium is a metal, chlorine is a non-metal, so they form a lattice structure of alternating Na+ and Cl- ions.
With S8, that only contains one element, sulfur, and it tells you that the formula is a molecule containing 8 sulfur atoms. They would be covalently bonded.
Sodium Nitrate - so the formula is NaNO3. You know that the nitrate ion is NO3-, and the sodium forms Na+, so you can see it is ionically bonded. The sodium, as a metal, wouldn't be part of a covalent molecule with the nitrate, although the nitrate part is covalently bonded.
never heard the term "simple molecular lattice" before. Molecules are generally small covalent structures. Lattice is a word normally used to describe the structure of an ionic compound. Can you give some examples of what is confusing you?

try here https://science-revision.co.uk/non_metals.html
https://science-revision.co.uk/A-level_ionic_compounds_structure.html

hope this helps a bit!!!
(edited 1 year ago)
Original post by Alevelhelp.1
Sodium chloride.
And s8.
And Sodium Nitrate.

sodium chloride has a giant ionic lattice.
sulfur has a simple molecular structure
sodium nitrate is also probably giant ionic lattice.

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