# What`s redox anyways?

### A tutor’s guide on teaching about oxidation-reduction problems

By Stephanie Yan, Jennifer Zhang, and Farnaz Dayani

 Key concepts

 understand terminology

 Understand general trends in oxidation states of various elements

 understand concept of valence electrons and that valence electrons does NOT always correspond with oxidation number

Student's difficulty

 Student is able to understand redox reactions with oxygen and hydrogen, but has difficulty with ones that don't only involve O 2and H +

 Student sometimes gets confused with words like "oxidation reaction, oxidized element, and oxidizing agent”

 student has not yet learned to balance redox equations

 First, make sure the student understands that:

 oxidation means gain of oxygen or loss of electrons

 reduction invovles loss of oxygen or gain of electrons

 Show a problem that includes gain or loss of oxygen

 Show solution reduction: CuO gets reduced

CuO+ H2  Cu + H2O(loss of “o”) gaining oxygen, SO3(2-) gets oxidized ,SO3(2-) + H2O= SO4(2-

)(gain of “o”)

 Show a problem that does not involves loss or gain of oxygen

 Show solution

EX: Zn + CuSO4= ZnSO4 + Cu

Zn(0) – 2e- -------Zn2+ lose electron, gets oxidized

CU2+ 2e- --------CU(0) gain electron, gets reduced, occurs reduction

 In solution, include that the element that is reduced is the oxidizing agent and the element that is oxidized is the reducing agent

 explain oxidation state and numbers (O is always 2-, H is usually +1, figure rest out from total compound/molecule's charge

 Explain how to solve for an element’s oxidation states in absence of O2and H+

 use boxes with arrows and letters up/down O(r)R(a), down/up R(r)O(a)

O.S

O

R

R

O

Electron Reaction Agent

 Love story between Mr. Orra and Ms. Rroa and flowers are e-

 you cannot marry yourself/ be a husband-wife so you can't be the oxidizing agent AND be oxidized. Therefore if you are oxidized, you are the reducing agent.

 LEO the lion says GER (can also be visual verbal)

 Lose Electron = Oxidation

 Gain Electron = Reduction

When you gain an electron, the charge is actually reduced because electrons are negative charge

 Story telling along with previous example of love story

(once upon a time, there was a guy named ORRA…………)