Calculate the oxidation number of chlorine to perchloric acid, HClO4, a strong oxidizing agent.
total load must = 0
perchlorate (ClO4-) = -1
hydrogen cation (H+) = 1+)
ClO4- = -1
Cl + 4O = -1
O has oxidation charge 2
then
Cl + 4 (-2) = -1
Cl + (-8) = -1
Cl = -1+8 = 7
so the degree of oxidation of chlorine is 7 in this case
Source(s): I paid attention during AP Química
the answer above is really confusing… the shortcut is like below
the total perchloric acid charge is 0.
no oxidation. of H is +1
no oxidation. of O2 is -2
we have to find the oxidation no. of Cl
since the total charge is 0 , I can write that 1 + x + (-2 X 4) =0
solve for x where x is the oxidation number. chlorine
you get x = +7.
PS always put the sign if it is positive or negative.. it is very important