Hey, I'm having trouble understanding the trends of the oxidation states for the first row of the transition metals -my prof said that Cu is the only metal that forms a stable +1 oxidation state. But, I've done a question in hmwrk that had Cu+1 as unstable with respect to disproportionation how can it be both stable and unstable? -The frost diagram for the transition metals has all (except Cu) with negative 2+/3+ oxidation states. Does this mean that the oxidation reaction M(metal)⇔Mz+ +ze- is thermodynamically favoured as the reduction couple (slope of the line) is negative? Thanks a lot!