Oxidation no. Of O in KCLO3?

1 Answer
Feb 19, 2018

In #"potassium chlorate"# we gots #Cl(+V)#...and #O(-II)#..and also #K(+I)#..

Explanation:

There is a nice series of halogen oxyanions....and as always the oxidation number is the charge left on the central atom when all the bonding pairs of electrons are broken with the charge assigned to the most electronegative atom. Oxygen is more electronegative than chlorine, so it get the electrons...and in each case we formally got #O(-II)#...

#Cl^(-)#, #"chloride"#, we gots #Cl(-I)#

#ClO^(-)#, #"hypochlorite"#, we gots #Cl(+I)#

#ClO_2^(-)#, #"chlorite"#, we gots #Cl(+III)#

#ClO_3^(-)#, #"chlorate"#, we gots #Cl(+V)#

#ClO_4^(-)#, #"perchlorate"#, we gots #Cl(+VII)#