Prussian Blue Flashcards
Rules for redox reaction
- make half reactions
- if there is an O2- on one side, replace that with a water molecule
- Balance all molecules except H and O (does NOT include water)
- Balance O with water and H with H+
- Add electrons to more positive side
- Balance both sides and cancel the electrons
- Combine them together
Substrate
surface where the reaction occurs (In our case the ITO glass)
What does the ITO cover on the glass do?
allows passage of electricity
Why do we need the ITO cover?
because glass is an electrical insulator, not a conductor
What is the white compound formed when the (-) touched the glass?
Everitt Salt (K4Fe4[Fe(CN)6]3Cl3)
Why do some experiments turn a yellowish colour when the (+) touched the glass?
A compound called prussian yellow may have been formed. For some people it simply turned dark blue and became opaque
Everitt Salt is a
reduction reaction
Prussian yellow is an
oxidization reaction
PB is a
transition metal complex (like EDTA)
What is current in the electrochemical sense?
the rate at which electrons flow
How can absorbance measurements determine the effectiveness of PB?
as absorbance increases, so does concentration (directly proportional to eachother), when the [ ] increases, so does the conductivity, which means more electrons are transferred during reactions, leading to a faster production of PB
Why did some experiments not turn clear or dark blue at all?
The concentration of KCl was too low, not enough conductivity for it to react
Percent Atom Economy formula
mass of product/mass of total reactants x 100%
What does higher atom economy mean?
more of the reactants are used, therefore less waste/incomplete substances made
Photochromic
change colour when hit with light (both UV and visible)
