Balance the following reaction in Basic media: Fe2+ + Cr2O7 2- = Fe3+ + Cr 3+? a

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Fe2+ + Cr2O7^2- --> Fe3+ + Cr3+ Fe2+ --> Fe3+ + 1e- 7H2O + Cr2O7^2- + 6e- --> 2Cr3+ + 14OH- ------------------- -------------------- ---------------------- 7H2O + Fe2+ + Cr2O7^2- --> Fe3+ + 2Cr3+ + 14OH- ello there this is a redox equation, not so simple. You must split the equation into two parts, then fuse those two parts together for a final equation. One part is a reduction equation and the other part is the oxidation equation. Part 1: Look at fe. It goes from 2+ to 3+. This you can see it has lost an electron, so it is the oxidation reaction. This part is simple reaction is just fe2+>fe3+ +e-. This adding of the electron balances the equation. Part 2: Look at Cr. Our equation for this is Cr2O72->Cr3+ This is not balanced. Cr2O72->2Cr3+. If it is not balanced at this point you add water. Look at your Oxygens. You need 7 on the right to balance them. Cr2O72->2Cr3+ + 7H2O But now your hydrogens aren't balanced. Add 14 to the left side. Cr2O72- +14H+> 2Cr3+7H2O Haha now your electrons aren't balanced! Left side: -2 +14=12 Right side: +6 (double coz there's 2 Cr) water has no charge so just 0. Now just add 6 electrons to left side and this part is done. So now we have our two parts to the equation 1. Fe2+>Fe3+ + e- 2. Cr2O72- +14H+ +6e->2Cr3+ +7H2O You look at your electrons. Whatever the number in front of the e- is, is the number you multiply other equation by. So (1.) is multiplied by 6 and (2.) is multiplied by 1. Now add 2 together. You can now take electrons out of equation. 6Fe2+ + Cr2O72- + 14H+>6Fe3+ + 2Cr3+ + 7H2O. Haha sorry for the length but here it is. The coefficient in front of the h2O is 7 and it is on the right side of the equation. I hope you understood this and I helped.

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