Question

Statement 1: When $ 2litres $ of oxygen gas reacts with $ 2litres $ of hydrogen completely, the limiting factor is the volume of the oxygen.
Statement 2: The coefficient in balanced equations of gaseous reactions give the volume relationships of the evolved gases.
A.Both statement 1 and statement 2 are correct and statement 2 is the correct explanation of statement 1
B.Both the statement 1 and statement 2 are correct and statement 2 is not the correct explanation of statement 1
C.Statement 1 is correct but statement 2 is not correct
D.Statement 1 is not correct but statement 2 is correct
E.Both the statement 1 and statement 2 are not correct

Answer 1

Hint: The precise amount of reactants required to react with another product can be determined from reaction stoichiometry. If the proper stoichiometric proportions of the reactants are not combined as shown by the balanced chemical equation, one of the reactants will be fully absorbed, and another will be left over.

Complete step by step answer:
Before analysing the first statement we should first learn about the term “limiting reagent”. The limiting reagent is the reactant that is fully consumed in a reaction, it restricts the reaction from proceeding so the reactant which is in excess quantity does not have any one left to react.
Now let’s analyse the first statement;
\[\,2{H_2}(g) + {O_2}(g) \to 2{H_2}O(l)\,\]
As this reaction happens, two hydrogen molecules and an oxygen molecule react specifically to create two molecules of water. Suppose 10 moles of hydrogen and 7 moles of oxygen are present. As the molar ratio of hydrogen and oxygen molecules is 2:1, once the reaction has happened entirely, one would be left over, which in this case will be oxygen. In order to produce 10 moles of water, all 10 moles of hydrogen will react with 5 moles of oxygen, leaving 2 moles of oxygen, as seen in the following equation:
\[\,2{H_2}(g) + {O_2}(g) \to 2{H_2}O(l)\,\]

$\,10\,$	$\,7\,$	$\,0\,$
$\, - 10\,$	$\, - 5\,$	$\, + 10\,$
$\,0\,$	$\,2\,$	$\,10\,$

So, in the above statement hydrogen is the exact limiting reagent and oxygen is the excess reagent. Hence, the statement 1 is not correct.

Now, let’s analyse the statement 2;
As per the ideal gas theorem, if the pressure and temperature are known, we can use the relationship between the quantities of gases (in moles) and their volumes (in litres) to measure the stoichiometry of reactions involving gases.
Also there is another law that talks about this matter which is the ‘Law of Combining Volumes’.
The first to discover this law of combining volumes was the prominent scientist Gay-Lussac, who observed this connection. He determined that under the same conditions of temperature and pressure, those gases which are products and reactions in a chemical reaction are calculated, then the amount of gas consumed / produced is proportional to the ratio between the gases or the ratio of the coefficients.
So, from the above explanation, it is clear that statement 2 is correct.

So, the correct answer is Option D.

Note:
There are two ways to calculate the limiting reagent. One approach is to find the mole ratio of the reactants used in the reaction and compare them. Another method is to measure the $ grams $ of products produced from the quantity of reactants given; the reactant producing the smallest quantity of product is the limiting reagent.