[chem] electrolysis intro

diff --git a/chem/electrochemistry.md b/chem/electrochemistry.md
index e439add9587c3d23697fcda047b94e9a57229244..8436dd6bf9070702684fcdc55d6f27d8ca41884e 100644 (file)
--- a/chem/electrochemistry.md
+++ b/chem/electrochemistry.md
@@ -80,3 +80,29 @@ Used for vehicles/long-lasting applications. ce{H2} may be replenished.
 - **Alkaline fuel cell** - ce{KOH(aq)} electrolyte, ce{H2(g)} from tank, ce{O2(g)} from atmosphere, water out of hydrogen side
 - **Acid fuel cell** - ce{H3PO4} electrolyte, water out of oxygen side
 
 - **Alkaline fuel cell** - ce{KOH(aq)} electrolyte, ce{H2(g)} from tank, ce{O2(g)} from atmosphere, water out of hydrogen side
 - **Acid fuel cell** - ce{H3PO4} electrolyte, water out of oxygen side
 

+## Electrolysis reactions
+
+- Opposite of reactions in electrochemical (galvanic) cells
+- Non-spontaneous
+- Electrical energy $\rightarrow$ chemical energy
+
+### Electroplating
+
+- For each ion going into plated object, an ion is replaced from the anode (+ve)
+- Electrolyte balances charges
+
+### Coulomb's law
+
+$$Q=It$$
+
+### Faraday's first law
+
+$$m \propto Q$$
+
+i.e. mass produced at cathode is proportional to charge supplied
+
+*Faraday* - charge on 1 mol of electrons = 96500 C.
+
+### Faraday's second law
+
+> To produce one mole of substance by electrolysis, a whole number of mole of electrons is needed