How to find the Oxidation Number for Cr in the Cr2O7 2- ion. (Dichromate ion)
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6 سال پیش
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To find the oxidation number
To find the oxidation number for Cr in Cr2O7 2- (the Dichromate ion), and each element in the ion, we use few simple rules and some simple math.
First, since the Dichromate ion has an overall charge of 2- we could say that the oxidation numbers in Cr2O7 2- need to add up to charge on the ion.
We write the oxidation number (O.N.) for elements that we know and use these to figure out oxidation number for Cr.
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GENERAL RULES
In an ion all Oxidation numbers must add up to to the ion charge.
Group 1 = +1
Group 2 = +2
Hydrogen with Non-Metals = +1
Hydrogen with Metals (or Boron) = -1
Fluorine = -1
Oxygen = -2 (except in H2O2 or with Fluorine)
Group 17(7A) = -1 except with Oxygen and other halogens lower in the group
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We know that Oxygen usually is -2 with a few exceptions. When Oxygen is in a peroxide, like H2O2 (Hydrogen peroxide), it has a charge of -1. When it is bonded to Fluorine (F) it has an oxidation number of +2.
Here it is bonded to Cr so the oxidation number on Oxygen is -2. Using this information we can figure out the oxidation number for the element Cr in Cr2O7 2-.
First, since the Dichromate ion has an overall charge of 2- we could say that the oxidation numbers in Cr2O7 2- need to add up to charge on the ion.
We write the oxidation number (O.N.) for elements that we know and use these to figure out oxidation number for Cr.
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GENERAL RULES
In an ion all Oxidation numbers must add up to to the ion charge.
Group 1 = +1
Group 2 = +2
Hydrogen with Non-Metals = +1
Hydrogen with Metals (or Boron) = -1
Fluorine = -1
Oxygen = -2 (except in H2O2 or with Fluorine)
Group 17(7A) = -1 except with Oxygen and other halogens lower in the group
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We know that Oxygen usually is -2 with a few exceptions. When Oxygen is in a peroxide, like H2O2 (Hydrogen peroxide), it has a charge of -1. When it is bonded to Fluorine (F) it has an oxidation number of +2.
Here it is bonded to Cr so the oxidation number on Oxygen is -2. Using this information we can figure out the oxidation number for the element Cr in Cr2O7 2-.
6 سال پیش
در تاریخ 1397/05/02 منتشر شده
است.
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