Question

Water produces hydrogen and oxygen in the ratio of (mole ratio):
A. 1:1
B. 2:3
C. 2:1
D. 1:2

Answer 1

Hint: The answer for this question includes the fact that the reaction of the decomposition of water molecules produces hydrogen and oxygen and by writing a balanced chemical equation, you can get the required answer.

Complete answer:
We have studied the basic concept of decomposition reaction in our lower classes of chemistry and also the factors that affect this decomposition reaction and also about the causes.
Now, let us refresh those concepts about what the decomposition reaction means and shall deduce the required answer by writing the balanced chemical equation.
- Decomposition reaction is basically defined as the reaction in which the compound that is a reactant splits up into two or more simpler components.
- Usually decomposition reaction is favoured by heat, electrolysis, microbial action and some other factors.
- There are three type of decomposition reaction defined in chemistry and they are:
- Thermal decomposition
- Electrolytic decomposition
- Photo decomposition
Now, water is decomposed in the electrolysis process. When the electric current is passed through the aqueous solution of water it decomposes into hydrogen and oxygen gases and the balanced reaction is given by,
\[2{{H}_{2}}O(l)\to 2{{H}_{2}}(g)+{{O}_{2}}(g)\]
Thus, by this balanced equation we can say that two moles of water produces two moles of hydrogen and one mole of oxygen.
Therefore, the water produces hydrogen and oxygen in the molar ratio of 2:1

Hence, the correct answer is option C) 2:1 .

Note:
Note that electrolytic decomposition is nothing but the decomposition reaction that occurs when an electric current is passed through and aqueous solution of a compound and these types of several decomposition reactions have a wide range of application in industries.