Answer:
-2 , -1
Step-by-step explanation:
H2PO4=-1
+1 × 2 + +5 + 4 ×O=-1
7+ 4O =-1
4O= -8
O = -2
H2O2=0
+1 × 2 +2 x O =0
2 + 2O=0
O= -1
(As the oxidation number of Hydrogen is +1 , and we have 2 hydrogen atoms so we multiply by 2 , while the oxidation number of P is +5 in this equation, also the compound as a whole equals -1 , then we do the steps as followed)
(while the other compound as a whole equals zero , and doing steps as followed)
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