Physics Athens 2016

Chemical standard (Fricke)

Determine  M = mole Fe 3+ /liter - Fe 3+ exhibits strong absorption peak at  = 304 nm, Fe 2+ not - measure UV transmissions through Fricke samples:

Fe 2+ in H 2

O

I 0

uv

before irradiation:

uv

after irradiation:

I

Fe 2+ and Fe 3+ in H 2 O

log(I 0

/I)

 M =

 = 2187 liter mole -1 cm -1

 ·L