Answer :
The oxidation state of oxygen (O) in
is, (+2)
The oxidation state of carbon (C) in
is, (+2)
The oxidation state of nitrogen (N) in
is, (-3)
Explanation :
Oxidation number : It represent the number of electrons lost or gained by the atoms of an element in a compound.
Oxidation numbers are generally written with the sign (+) and (-) first and then the magnitude.
When the atoms are present in their elemental state then the oxidation number will be zero.
Rules for Oxidation Numbers :
The oxidation number of a free element is always zero.
The oxidation number of a monatomic ion equals the charge of the ion.
The oxidation number of Hydrogen (H) is +1, but it is -1 in when combined with less electronegative elements.
The oxidation number of oxygen (O) in compounds is usually -2, but it is -1 in peroxides.
The oxidation number of a Group 1 element in a compound is +1.
The oxidation number of a Group 2 element in a compound is +2.
The oxidation number of a Group 17 element in a binary compound is -1.
The sum of the oxidation numbers of all of the atoms in a neutral compound is zero.
The sum of the oxidation numbers in a polyatomic ion is equal to the charge of the ion.
(a) The given compound is,
![OF_2](https://img.qammunity.org/2021/formulas/chemistry/middle-school/8q0s5wfaf7ezks4xmi1hlcrtpukxswfvkd.png)
Let the oxidation state of 'O' be, 'x'
![x+2(-1)=0\\\\x-2=0\\\\x=+2](https://img.qammunity.org/2021/formulas/chemistry/high-school/lsrmeukmawddaas907imh6frrjk91lzlwp.png)
The oxidation state of oxygen (O) in
is, (+2)
(b) The given compound is,
![CO](https://img.qammunity.org/2021/formulas/chemistry/college/fyji4qz02eofzpk1e8g36rfbx4azwpfyt5.png)
Let the oxidation state of 'C' be, 'x'
![x+(-2)=0\\\\x-2=0\\\\x=+2](https://img.qammunity.org/2021/formulas/chemistry/high-school/fsenmgl54bf092rz1ak34qsq6eebhc3mdx.png)
The oxidation state of carbon (C) in
is, (+2)
(c) The given compound is,
![K_3N](https://img.qammunity.org/2021/formulas/chemistry/high-school/x7qd892bd0l14s6qbbm3w7jvwcudu9eeot.png)
Let the oxidation state of 'N' be, 'x'
![3(+1)+x=0\\\\3+x=0\\\\x=-3](https://img.qammunity.org/2021/formulas/chemistry/high-school/1t112r2am4dvjlc37nd3hhmji70nta57kc.png)
The oxidation state of nitrogen (N) in
is, (-3)