Question

Reduction involves

• A. Addition of Hydrogen
• B. Addition of any electropositive element
• C. Removal of oxygen
• D. Removal of any electronegative element

Answer 1

Answer: (A), (B), (C), (D)

The correct options are
A Addition of Hydrogen
B Addition of any electropositive element
C Removal of oxygen
D Removal of any electronegative element

Reduction is the process of addition of hydrogen or hydrogen or any electropositive element or group or removal of oxygen or any electronegative element or group. For example:
a. $H_2\left(g\right)+C{l}_2\left(g\right)\stackrel{\left[R\right]}{\to }2HCl\left(g\right)\left(Additionofhydrogen\right)$
b. $2HgC{l}_2\left(aq\right)+SnC{l}_2\left(aq\right)\stackrel{\left[R\right]}{\to }H{g}_{2}C{l}_2\left(s\right)+SnC{l}_4\left(aq\right)$
(Addition of electropositive element)
c. $ZnO\left(s\right)+C\left(s\right)\stackrel{\left[R\right]}{\to }Zn\left(s\right)+CO\left(g\right)$
(Removal of oxygen)
d. $2FeC{l}_3\left(aq\right)+H_{2}S\left(g\right)\stackrel{\left[R\right]}{\to }FeC{l}_2\left(aq\right)+2HCl\left(aq\right)+S\left(s\right)$
(Removal of electronegative element)
A more general definition is:
Reduction : It is a process in which an atom or a group of atoms taking part in a chemical reaction gains one or more electrons.