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Simple molecular or Giant Covalent?

I'm really confused on how to know whether something is a Gant Covalent Structure of whether it's a simple molecular structure. For example, how is C2H5OH a simple molecular structure? I really don't understand.
Ethanol? Well... Simple molecular means you don't have covalent bonds between each C2H5OH, they are standalone. The covalent bonds are WITHIN C2H5OH i.e. between the Cs, Hs and O -- not between multiple molecules of C2H5OH.

Giant covalent such as graphite has an indefinite number of atoms i.e. carbons all tied together sharing electrons. C2H5OH has 9 atoms, it's hardly going to be "giant"... that's another way of looking at it :lol:
Reply 2
Original post by Flying Cookie
Ethanol? Well... Simple molecular means you don't have covalent bonds between each C2H5OH, they are standalone. The covalent bonds are WITHIN C2H5OH i.e. between the Cs, Hs and O -- not between multiple molecules of C2H5OH.

Giant covalent such as graphite has an indefinite number of atoms i.e. carbons all tied together sharing electrons. C2H5OH has 9 atoms, it's hardly going to be "giant"... that's another way of looking at it :lol:


oh okay aha thanks. But then how is S8 a giant covalent structure if it only has 8 atoms? :s-smilie:
Original post by _Aqsxo
oh okay aha thanks. But then how is S8 a giant covalent structure if it only has 8 atoms? :s-smilie:


Maybe because they're all the same type of atom rather than multiple elements. Ultimately you should learn the bonding type for each compound or molecule!
Original post by _Aqsxo
I'm really confused on how to know whether something is a Gant Covalent Structure of whether it's a simple molecular structure. For example, how is C2H5OH a simple molecular structure? I really don't understand.



Covalent bonds are only formed between 2 non-metals. S8 is a non-metal, Sulfur is a non-metal atom.
There are 2 main types of covalent bonds:

simple molecular

giant covalent


Simple molecular contains only very few atoms held together by covalent bond. A simple example would be CO2
(edited 9 years ago)
Reply 5
Original post by Megan_90
Covalent bonds are only formed between 2 non-metals. S8 is a non-metal, Sulfur is a non-metal atom, so S8 has giant covalent bond.
There are 2 main types of covalent bonds:

simple molecular

giant covalent


Simple molecular contains only very few atoms held together by covalent bond. A simple example would be CO2


yes i understand that but i don't understand how C2H5OH is a simple molecular as you're saying simple molecular means very few atoms held together by covalent bonds but S8 is 8 atoms and it's a giant covalent but C2H5OH is 9 atoms and is simple molecular :s-smilie:
Original post by _Aqsxo
yes i understand that but i don't understand how C2H5OH is a simple molecular as you're saying simple molecular means very few atoms held together by covalent bonds but S8 is 8 atoms and it's a giant covalent but C2H5OH is 9 atoms and is simple molecular :s-smilie:



why did you think that S8 is giant covalent? S8 is NOT giant covalent. its the other way around. C2H5OH is giant covalent and S8 is simple molecular.
Reply 7
Original post by Megan_90
why did you think that S8 is giant covalent? S8 is NOT giant covalent. its the other way around. C2H5OH is giant covalent and S8 is simple molecular.


Everyone i've asked says that C2H5OH Is simple molecular including the person above you..
Reply 8
S8 is not giant covalent. Only 8 S are tied together using covalent bonds - this is hardly giant.

I believe the only giant covalent structures you will encounter are carbon (diamond and graphite). Look at the way they are drawn and you will see that they can extend like this 'forever'.

And Ethanol is simple molecular because one complete molecule is formed using 9 atoms. You can have many molecules of ethanol but they would not be covalently bonded together (rather vander waals forces).

giant molecular - huge number of atoms tied together by strong covalent bonds forming a huge lattice
simple molecular - a few atoms tied together by strong covalent bonds forming a molecule.

H2 - simple molecular
H20 - simple molecular

(now NaCl is a giant structure (forms a huge lattice) but it's ionic).

Can't think of any giant covalent but diamond and graphite.

[look up: simple molecular, giant covalent, ionic and metallic structures. Some things also just exits as single atoms like noble gases (with vander waals forces between atoms)].
(edited 9 years ago)
Reply 9
S8 is not giant. Neither is ethanol. Both have molecular formulae, which tells you how many atoms there are in the molecule. You cannot know how many atoms there are in giant covalent substances (note I do not call them molecules, although some refer to them as macromolecules, I don't like the term).

The giant moleculars are graphite, diamond, silicon, silicon dioxide, silicon carbide, boron and a few (ish) others. Although RMIM is right, the two forms of carbon are pretty much the only ones you'll come across.

The other thing to look out for is melting/boiling point data (or state of matter). If it is high (thousands of degrees) then it'll be giant. If it is relatively low (up to a few hundred) it'll be simple.
Reply 10
Original post by RMIM
S8 is not giant covalent. Only 8 S are tied together using covalent bonds - this is hardly giant.

I believe the only giant covalent structures you will encounter are carbon (diamond and graphite). Look at the way they are drawn and you will see that they can extend like this 'forever'.

And Ethanol is simple molecular because one complete molecule is formed using 9 atoms. You can have many molecules of ethanol but they would not be covalently bonded together (rather vander waals forces).

giant molecular - huge number of atoms tied together by strong covalent bonds forming a huge lattice
simple molecular - a few atoms tied together by strong covalent bonds forming a molecule.

H2 - simple molecular
H20 - simple molecular

(now NaCl is a giant structure (forms a huge lattice) but it's ionic).

Can't think of any giant covalent but diamond and graphite.

[look up: simple molecular, giant covalent, ionic and metallic structures. Some things also just exits as single atoms like noble gases (with vander waals forces between atoms)].


SiO2 is also giant covalent! but thank you for clearing that up for me!
Reply 11
Original post by Pigster
S8 is not giant. Neither is ethanol. Both have molecular formulae, which tells you how many atoms there are in the molecule. You cannot know how many atoms there are in giant covalent substances (note I do not call them molecules, although some refer to them as macromolecules, I don't like the term).

The giant moleculars are graphite, diamond, silicon, silicon dioxide, silicon carbide, boron and a few (ish) others. Although RMIM is right, the two forms of carbon are pretty much the only ones you'll come across.

The other thing to look out for is melting/boiling point data (or state of matter). If it is high (thousands of degrees) then it'll be giant. If it is relatively low (up to a few hundred) it'll be simple.

thank you so much :tongue:
Original post by RMIM
S8 is not giant covalent. Only 8 S are tied together using covalent bonds - this is hardly giant.

I believe the only giant covalent structures you will encounter are carbon (diamond and graphite). Look at the way they are drawn and you will see that they can extend like this 'forever'.

And Ethanol is simple molecular because one complete molecule is formed using 9 atoms. You can have many molecules of ethanol but they would not be covalently bonded together (rather vander waals forces).

giant molecular - huge number of atoms tied together by strong covalent bonds forming a huge lattice
simple molecular - a few atoms tied together by strong covalent bonds forming a molecule.

H2 - simple molecular
H20 - simple molecular

(now NaCl is a giant structure (forms a huge lattice) but it's ionic).

Can't think of any giant covalent but diamond and graphite.

[look up: simple molecular, giant covalent, ionic and metallic structures. Some things also just exits as single atoms like noble gases (with vander waals forces between atoms)].


thank you in advance
If something like He doesn't havef covalent bonds in it, what is it than?
Since it has full outer shell it does not form bonds it just exists as a single atom. Therefore the only bonds it can form are weak interMolecular bonds.

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