Question

latimer diagram arsenic pH=7

Answer 1

The following half reaction with their respect potential apply for arsenic:

These potentials are at pH=0, using the nernst equation you can calculate the values at pH=7

<------ Q is the reaction quotient, but in this case you only have to change the H+, n is the electrons trasferred in the half reaction

<-----firts reaction

<-----second

<-----third

The latimer diagram is the representation of the species in the decending order, from most oxidize to most reduced, and with their potentials:

This goes in the following order As(V), As(III), As⁰ , As^-3