rsidofdhoidsh
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Can someone help me with this please?

Explain which species is reduced in the reaction between magnesium and iron chloride.
3 Mg + 2 FeCl3 ⟶ 2 Fe + 3 MgCl2
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hilary08
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I would say the first thing to do is remember that reduction is gain of electrons. Iron is reduced because the charge on iron in FeCl3 is +3 and it gains electrons to form an overall charge of 0. I hope this helps
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Deggs_14
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Iron has been reduced as its oxidation state has decreased from +3 to 0.
Last edited by Deggs_14; 7 months ago
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rsidofdhoidsh
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(Original post by hilary08)
I would say the first thing to do is remember that reduction is gain of electrons. Iron is reduced because the charge on iron in FeCl3 is +3 and it gains electrons to form an overall charge of 0. I hope this helps
How do you know that the charge of iron in FeCl3 is +3?
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Adambrl
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(Original post by rsidofdhoidsh)
How do you know that the charge of iron in FeCl3 is +3?
Because your should know that chlorine has an oxidation state of -1 except if it’s combined with oxygen or a halogen higher than it in its group.
This is true for all halogens. (except fluorine, see @Deggs_14 below correcting my mistake)

Since you have 3 Cl with each having an oxidation state of -1 your total would come to -3.
And since the compound itself has no charge, you can assume that the oxidation number of the compound equals 0.

Therefore, Fe has to have an oxidation state of +3 as:

-3 + 3 = 0.

Hope this helps.
Last edited by Adambrl; 7 months ago
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Deggs_14
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(Original post by rsidofdhoidsh)
How do you know that the charge of iron in FeCl3 is +3?
Because this is an ionic compound with three Cl- ions and one Fe 3+ ion. The oxidation states are the ionic charges.
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rsidofdhoidsh
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(Original post by Adambrl)
Because your should know that chlorine has an oxidation state of -1 except if it’s combined with oxygen or a halogen higher than it in its group.
This is true for all halogens.

Since you have 3 Cl with each having an oxidation state of -1 your total would come to -3.
And since the compound itself has no charge, you can assume that the oxidation number of the compound equals 0.

Therefore, Fe has to have an oxidation state of +3 as:

-3 + 3 = 0.

Hope this helps.
Alright, I think I understand it now. Ty!
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rsidofdhoidsh
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(Original post by Deggs_14)
Because this is an ionic compound with three Cl- ions and one Fe 3+ ion. The oxidation states are the ionic charges.
Ty
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Deggs_14
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(Original post by Adambrl)
Because your should know that chlorine has an oxidation state of -1 except if it’s combined with oxygen or a halogen higher than it in its group.
This is true for all halogens.

Since you have 3 Cl with each having an oxidation state of -1 your total would come to -3.
And since the compound itself has no charge, you can assume that the oxidation number of the compound equals 0.

Therefore, Fe has to have an oxidation state of +3 as:

-3 + 3 = 0.

Hope this helps.
The oxidation state of fluroine is always -1, even in interhalogen compounds and when bonded covalently with other non-metals.
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rsidofdhoidsh
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(Original post by Deggs_14)
The oxidation state of fluroine is always -1, even in interhalogen compounds and when bonded covalently with other non-metals.
chlorine*?
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Adambrl
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(Original post by rsidofdhoidsh)
chlorine*?
Referring to my wrongful claim that all halogens are -1 except when combined with Oxygen or a halogen higher than it in the group. Fluorine is an exception with it always being -1
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Deggs_14
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(Original post by rsidofdhoidsh)
chlorine*?
Chlorine undergoes disproportionation with water or alkali under various conditions into positive oxidation states, like NaOCl used in bleaches and detergents.
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rsidofdhoidsh
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(Original post by Adambrl)
Referring to my wrongful claim that all halogens are -1 except when combined with Oxygen or a halogen higher than it in the group. Fluorine is an exception with it always being -1
Ohh alrighty
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