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Redox Reactions formula sheet

Every formula in the Redox Reactions chapter for JEE Main, with one line on when it applies. Topic 1 is open to everyone; sign in free to read all 23 and download the PDF.

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Oxidation and reduction

Oxidation and reduction
Zn→ZnX2++2 eX− (oxidation)CuX2++2 eX−→Cu (reduction)\begin{aligned}&\ce{Zn -> Zn^{2+} + 2e-}\ (\text{oxidation})\\&\ce{Cu^{2+} + 2e- -> Cu}\ (\text{reduction})\end{aligned}
Oxidation: loss of e−e^-, ON rises. Reduction: the reverse. Both occur together.
Is it redox?
4× asked, last 2024
redox  ⟺  at least one element changes its ON\text{redox}\iff\text{at least one element changes its ON}
Not redox: neutralisation, precipitation, OX2→OX3\ce{O2 -> O3}, CrX2OX7X2−⇌CrOX4X2−\ce{Cr2O7^{2-} <=> CrO4^{2-}}, CrOX2ClX2\ce{CrO2Cl2}.
Oxidant and reductant
6× asked, last 2024
oxidant+ne−→reduced formreductant→oxidised form+ne−\begin{aligned}&\text{oxidant}+ne^-\to\text{reduced form}\\&\text{reductant}\to\text{oxidised form}+ne^-\end{aligned}
FeIX3\ce{FeI3}, CuIX2\ce{CuI2} unknown: the cation oxidises its own anion. Takes a reductant to a higher ON: stronger oxidant.
Range of ON
3× asked, last 2024
highest ON=v,lowest ON=v−8\text{highest ON}=v,\qquad \text{lowest ON}=v-8
Non-metals of groups 14–17 (not O, F). Highest: oxidant only; lowest: reductant only. Metals: lowest is 0.
Hydrogen peroxide
9× asked, last 2023
HX2OX2→OX2+2 HX++2 eX− (reductant)HX2OX2+2 HX++2 eX−→2 HX2O (oxidant)\begin{aligned}&\ce{H2O2 -> O2 + 2H+ + 2e-}\ (\text{reductant})\\&\ce{H2O2 + 2H+ + 2e- -> 2H2O}\ (\text{oxidant})\end{aligned}
O is −1. Oxidises FeX2+\ce{Fe^{2+}} in acid; reduces MnOX4X−\ce{MnO4-}, giving off OX2\ce{O2}.

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Practise Redox Reactions

18 more formulas in 4 topics

Oxidation number, Types of redox reactions, Balancing and Redox titrations. Read the first part free. Sign in free with Google to read the rest and download the PDF.

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Oxidation number

  • ON rules9×
  • Oxoacids
  • Oxygen and hydrogen2×
  • Complexes and carbonyls4×
  • Average vs structural ON2×

Types of redox reactions

  • Combination and decomposition3×
  • Displacement4×
  • Disproportionation14×
  • Comproportionation2×

Balancing

  • Ion-electron method12×
  • Basic medium
  • Oxidation-number method6×

Redox titrations

  • Mole ratios (acid)7×
  • n-factor8×
  • n-factor in disproportionation
  • Permanganate by medium19×
  • Dichromate in acid9×
  • Iodometry4×

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