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प्रश्न
When acidified \[\ce{K2Cr2O7}\] solution is added to \[\ce{Sn^{2+}}\] salts then \[\ce{Sn^{2+}}\] changes to ______.
पर्याय
\[\ce{Sn}\]
\[\ce{Sn^{3+}}\]
\[\ce{Sn^{4+}}\]
\[\ce{Sn+}\]
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उत्तर
When acidified \[\ce{K2Cr2O7}\] solution is added to \[\ce{Sn^{2+}}\] salts then \[\ce{Sn^{2+}}\] changes to \[\ce{Sn^{4+}}\].
Explanation:
\[\ce{Cr2O7^{2-} + 14H^+ + 3Sn^{2+} -> 2Cr^{3+} + 3Sn^{4+} + 7H2O}\]
In the above redox reaction, oxidation of \[\ce{Sn^{2+}}\] is taking place. It gets converted to \[\ce{Sn^{4+}}\] whereas, reduction of chromium is occurring from +6 oxidation state to +3.
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