Question

Cd2+ + Ni2++ 2H20Cd + NiO2+ 4H In the above reaction, the oxidation state of nickel changes from to How many electrons are transferred in the reaction?

Answer 1

The oxidation state in NiO2 is +4 X+2*-2=0 X=+4 Thus the oxidation state change from +2 to +4 Ni 2+ = Ni 4+ + 2e Number of electrons = 2 NH2OH Assume that the oxidation number of nitrogen is X X+3+(-2)=0 X+3-2=0 X+1=0 X=-1 N2H4 Assume that the oxidation number of nitrogen is X 2X+4=0 X=-4/2 X=-2 Oxidation number change from -1 to +1 Number of electrons = 2 3. Fe2+ = Fe3+ +e- Thus the oxidation state change from +2 to +3 Number of electrons = 1 Oxidation-reduction reaction is known as redox reaction. In these types of reaction one reactant is oxidized and another is reduced. Oxidation: Oxidation is a process in which either 1 or all following changes occurs: 1. In the oxidation, gaining of oxygen atoms occurred. 2. In the oxidation process oxidation number will increased. 3. In the oxidation process; loss of hydrogen atom occurred. 4. In the oxidation process; loss of electrons occurred. Reduction: Reduction is a process in which either 1 or all following changes occurs: 1. In the reduction process; loss of oxygen atoms occurred. 2. In the reduction process, oxidation number will decrease. 3. In the reduction process hydrogen atom are gained. 4. In the reduction process electrons are gained. To calculate the oxidation uses the following rule as follows: Total positive oxidation number + Total negative oxidation number = net charge Generally all atoms will lose, gain or share electrons to attain 8 valence electrons; the electron configuration of the nearest noble element. Oxidation state: Oxidation number is a numerical value which represents the elemental charge on the central metal atom of a complex ion. In the general the oxidation number of hydrogen and all alkaline metal is