Some chemical reactants are listed in the table below. Complete the table by filling in the oxidation state of the highlighted atom.
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Answer:
1. Cu = +2
2. O = – 2
3. C = +2
4. N = 0
Explanation:
Note:
A. The oxidation state of oxygen is always – 2 except in peroxides where it is – 1.
B. The oxidation state of Hydrogen is always +1 except in metallic hydrides where it is – 1.
Now let us solve the question given above.
1. CuO = 0 (ground state)
Cu + O = 0
O = – 2
Cu + (– 2) = 0
Cu – 2 = 0
Collect like terms
Cu = 0 + 2
Cu = +2
2. H2O = 0 (ground state)
2H + O = 0
H = +1
2(1) + O = 0
2 + O = 0
Collect like terms
O = 0 – 2
O = – 2
3. CO = 0 (ground state)
C + O = 0
O = – 2
C + (– 2) = 0
C – 2 = 0
Collect like terms
C = 0 + 2
C = +2
4. N2 = 0 (ground state)
2N = 0
Divide both side by 2
N = 0/2
N = 0