Question

What will be the value of x, y and z in the following equation -
$H_2{C}_2{O}_4+x{H}_2{O}_2\to yC{O}_2+z{H}_{2}O$

• A. 2, 1, 2
• B. 1, 2, 2
• C. 2, 2, 1
• D. None

Answer 1

The correct option is B 1, 2, 2

(i) The half reaction for oxidation is, $H_2{C}_2{O}_4\to C{O}_2$
Balancing carbon atoms on both sides, $H_2{C}_2{O}_4\to 2C{O}_2$
Balancing hydrogen atoms on both sides,
$H_2{C}_2{O}_4\to 2C{O}_2+2H^{+}$
Balancing charge on both the sides
$H_2{C}_2{O}_4\to 2C{O}_2+2H^{+}+2e^{-}$ (balanced)

(ii) The half reaction for reduction is -
$H_2{O}_2\to H_{2}O$
Balancing oxygen atoms on both sides,
$H_2{O}_2\to 2H_{2}O$
Balancing hydrogen atoms
$H_2{O}_2+2H^{+}\to 2H_{2}O$
Balancing the charge,
$H_2{O}_2+2H^{+}+2e^{-}\to 2H_{2}O$ (balanced)
Now, adding both equation,
$H_2{C}_2{O}_4+H_2{O}_2\to 2C{O}_2+2H_{2}O$
This is balanced equation.
Hence, $x=1,y=2,z=2$.