+6 for Cr, -2 for each O in Cr2O72-
oxidation number for oxygen is -2 so 7 of them makes -14 in total but the compound has an overall charge of 2- so therefore +12 is required. As there are two chromium then the oxidation number for each one is +6
2x+(3*-2)=0
2x-6=0
x=3
x=cr ions
Chromium takes +III oxidation state in this compound.
The oxidation number of Cr in CrO3 is +6
-2 for each O, +6 for each Cr
O.S. of Cr = +4
3
6
+3 for Cr and -2 for O
+2 for Ca, +6 for Cr, -2 for each O
In CrBr (chromium monobromide) Cr would have an oxidation number of +1. This compound is not known perhaps you meant CrBr3, where chromium has an oxidation number of +3
Cr is a transition metal and has a variation of oxidation number from 0 in the elemental state to +6 in the dichromate ion.
In Cr2O72- chromium (Cr) has an oxidation number of 6+ while oxygen has an oxidation number of 2-.
+3 for Cr and -2 for O
+2 for Ca, +6 for Cr, -2 for each O
In CrBr (chromium monobromide) Cr would have an oxidation number of +1. This compound is not known perhaps you meant CrBr3, where chromium has an oxidation number of +3
Cr is a transition metal and has a variation of oxidation number from 0 in the elemental state to +6 in the dichromate ion.
In Cr2O72- chromium (Cr) has an oxidation number of 6+ while oxygen has an oxidation number of 2-.
As with any other element, the oxidation number of Cr depends on whether and how it is chemically bonded. The oxidation number of pure elements is arbitrarily defined to be 0. In compounds, Cr has oxidation numbers of +2, +3, and +6, depending on the compound.
The answer is +6
+6
+6
+6 for Cr
O.S. of Cr = +6
6+