The oxidation number of cr in cr^3- is?
To determine the oxidation number of chromium (Cr) in the compound Cr^3-, we need to consider the charge of the anion.
The formula Cr^3- indicates that the compound has a negative 3 charge. The total charge of the anion suggests that the three negatively charged species (in this case, electrons) are required to balance the charge.
Since the overall charge is negative, and each electron has a charge of -1, the Cr ion must have a positive oxidation state that adds up to -3.
To find the oxidation number of chromium, we divide the -3 charge among the three atoms. We divide -3 by 1 (since there is only one chromium atom in this compound) to get -3/1 = -3.
Therefore, the oxidation number of Cr in Cr^3- is +3.