Answer : The balanced chemical equation is,
The coefficient for is, 4 and on reactant side of the equation is present.
Explanation :
Rules for the balanced chemical equation in basic solution are :
- First we have to write into the two half-reactions.
- Now balance the main atoms in the reaction.
- Now balance the hydrogen and oxygen atoms on both the sides of the reaction.
- If the oxygen atoms are not balanced on both the sides then adding water molecules at that side where the more number of oxygen are present.
- If the hydrogen atoms are not balanced on both the sides then adding hydroxide ion at that side where the less number of hydrogen are present.
- Now balance the charge.
The half reactions in the basic solution are :
Reduction : ......(1)
Oxidation : .....(2)
Now multiply the equation (1) by 2 and then added both equation, we get the balanced redox reaction.
The balanced chemical equation in a basic solution will be,
Thus, the coefficient for is, 4 and on reactant side of the equation is present.
Answer: "milk of magnesia" .
_______________________________________________________
The answer is A. The pH decreases
At room temperature, number of moles of distilled water is 1 x10^-7. Hope it cleared your doubt.