What are the oxidation states of phosphorus in the following: H3 PO3,PCl3 , Ca3 P2 , Na3 PO4 , POF3

Explanation

i Let the .Ox., state of .P. be .x. in .H_2 PO_3. .[3+1+x+3-2=0.
.+3 div x-6 y=0 x=+3.
ii PCI,
.1+, x+3-1=0.
.x=+3.
iii
.e+2+2 x=0.
.2 x=-6: x=-3.
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