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Oxygen and iron

Hey, this is really straight forward but i dont get it.
If O2 is a ditomic molecule. And Fe is a element in the periodic table. Is that an atom? Or moleule? And if an atom how does it become a molecule.

Ans since heam binds with oxygen. Because the charges need to balance. Would it be FeO2 or FeO but then the charges wont balannce. And is Oxygen O2- or O(2) 2- but theb i dont get this. Can someone explain roughly i cant recap thanks!
Reply 1
Original post by Tanyme
Hey, this is really straight forward but i dont get it.
If O2 is a ditomic molecule. And Fe is a element in the periodic table. Is that an atom? Or moleule? And if an atom how does it become a molecule.

Ans since heam binds with oxygen. Because the charges need to balance. Would it be FeO2 or FeO but then the charges wont balannce. And is Oxygen O2- or O(2) 2- but theb i dont get this. Can someone explain roughly i cant recap thanks!


transition elements have multiple oxidation states.fe(iron) is a transition element so its charges can be 2+ or 3+ as it lies between the 2 and 3 group of the periodic table.for eg,Fe2(SO4)3,the charge of iron is 3+ and in FeO2,it is 2+
Reply 2
Original post by Tanyme
Hey, this is really straight forward but i dont get it.
If O2 is a ditomic molecule. And Fe is a element in the periodic table. Is that an atom? Or moleule? And if an atom how does it become a molecule.

Ans since heam binds with oxygen. Because the charges need to balance. Would it be FeO2 or FeO but then the charges wont balannce. And is Oxygen O2- or O(2) 2- but theb i dont get this. Can someone explain roughly i cant recap thanks!


you're also confused about the atom and molecule consist.
Atom is the smallest unit of an existing particle
molecule-made of two or more atoms joined together
element-a pure substance that cannot be broken down or simplified
Oxygen alone in a periodic table is an atom,but when covalently joined to another Oxygen molecule,forms a molecule.
https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.topperlearning.com%2Fanswer%2Fwhat-is-the-difference-between-atoms-molecules-and-elements%2F7urm5b11&psig=AOvVaw1-jBGRMbXPdmNLvTwRMKMC&ust=1680718940042000&source=images&cd=vfe&ved=0CBEQjhxqFwoTCKCPpY3skP4CFQAAAAAdAAAAABAI
chck this link too as well...hope this helps!
(edited 11 months ago)
Reply 3
Original post by Tanyme
Hey, this is really straight forward but i dont get it.
If O2 is a ditomic molecule. And Fe is a element in the periodic table. Is that an atom? Or moleule? And if an atom how does it become a molecule.

Ans since heam binds with oxygen. Because the charges need to balance. Would it be FeO2 or FeO but then the charges wont balannce. And is Oxygen O2- or O(2) 2- but theb i dont get this. Can someone explain roughly i cant recap thanks!

Yes, O2 is a diatomic molecule (O=O) it consists of two oxygen atoms covalently bonded to each other (a double bond in fact).

An ion is an atom that has gained or lost electrons. A molecule is a group of two or more (a fixed number) atoms bonded (generally covalently) to each other. An atom is… erm… a very very small blob. Consists of a nucleus (containing protons and neutrons (unless it it hydrogen, which just has one proton)) surrounded by electrons.

Like oxygen, iron is an element. The forms in which it exists consist of just one type of atom (each atom has the same number of protons, i.e. the same element). As a solid, Fe exists as a giant metallic structure a lattice of positive ions surrounded by a sea of delocalised electrons (see this handy chemguide page for more info: https://www.chemguide.co.uk/14to16/atoms/metallic.html).
Iron is a transition metal, and transition metals can exhibit more than one oxidation state (i.e. more than one charge) iron typically can be iron(II) or iron(III) (Fe2+ or Fe3+).

Haem is a bit more complicated than just ionic bonding. Essentially the oxygen (O=O) molecule coordinates to the iron centre, through a lone pair of electrons on one of the oxygens. I'm not sure what level you are studying, so don't want to over-complicate things!
But chemguide has a little section on haemoglobin: https://chemguide.co.uk/inorganic/complexions/whatis.html (scroll down to the bit about quadridentate ligands)
And this page gives a decent overall picture of what is happening: https://chem.libretexts.org/Bookshelves/General_Chemistry/Book%3A_Structure_and_Reactivity_in_Organic_Biological_and_Inorganic_Chemistry_(Schaller)/V%3A__Reactivity_in_Organic_Biological_and_Inorganic_Chemistry_3/04%3A_Oxygen_Binding_and_Reduction/4.02%3A_Oxygen_Binding (don't worry about all the details!! But the images do help to give a bit of an idea :smile:)

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