PLEAAAASE HELP CHEM
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Answer:
5. +5
6. +7
Explanation:
The oxidation state can be obtained as follow:
5. Oxidation state of oxygen, O = –2
Oxidation state of phosphorus, P =?
P3O10 = –5
3P + 10O = –5
3P + (10 x –2) = –5
3P – 20 = –5
Collect like terms
3P = –5 + 20
3P = 15
Divide both side by 3
P = 15/3
P = +5
Therefore, the oxidation state of P in P3O10^5- is +5
6. Oxidation state of oxygen, O = –2
Oxidation state of manganese, Mn =.?
Mn2O7 = 0
2Mn + 7O = 0
2Mn + (7 x –2) = 0
2Mn – 14 = 0
Collect like terms
2Mn = 14
Divide both side by 2
Mn = 14/2
Mn = +7
Therefore, the oxidation state of Mn in Mn2O7 is +7