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प्रश्न
Write the formula of an oxo-anion of Chromium (Cr) in which it shows the oxidation state equal to its group number
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उत्तर
Formula of oxo-anion of chromium (Cr) in which it shows the oxidation state equal to its group number (6) is `Cr_2O_7^(2-)`
2Cr + (-2 ×7) = -2
2Cr - 14 = -2
2Cr = 12
Cr = +6
Oxidation of Cr in `Cr_2O_7^(2-)`is +6 which is equal to its group number 6.
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