Animated Solution for Chemistry - Organic Chemistry: The transformation occurring in Duma's method is given below $C_7{H}_{7}N+\left(2x+\frac{y}{2}\right)CuO⟶xC{O}_2+\frac{y}{2}{H}_{2}O+\frac{z}{2}{N}_2+\left(2x+\frac{y}{2}\right)Cu$ The value of $y$ is ......... . (Integer answer)

Duma's method is a classic technique used for the quantitative estimation of nitrogen in organic compounds. In this process, a known mass of the organic compound is heated with excess copper(II) oxide ($CuO$) in an atmosphere of carbon dioxide.

The carbon and hydrogen in the compound are oxidized to carbon dioxide and water, respectively, while the nitrogen is released as free nitrogen gas.

To solve this problem, we don't need to memorize complex formulas. We just need to rely on a fundamental law of chemistry: the Principle of Atom Conservation (POAC).

This principle states that atoms can neither be created nor destroyed in a chemical reaction. Therefore, the total number of atoms of a specific element on the reactant side must perfectly match the total number of atoms of that same element on the product side.

Let's apply this principle specifically to the hydrogen atoms in our given equation:

First, we examine the reactant side. The only molecule containing hydrogen is our starting organic compound, $C_7{H}_{7}N$. By simply looking at its chemical formula, we can see that it contains exactly 7 hydrogen atoms.

Next, we shift our focus to the product side. All the hydrogen from the organic compound has been converted into water ($H_{2}O$). The stoichiometric coefficient for water in the balanced equation is given as $\frac{y}{2}$.

Since each water molecule contains 2 hydrogen atoms, the total number of hydrogen atoms on the product side is:

Now, we equate the number of hydrogen atoms from both sides of the reaction:

And there we have it! The value of $y$ is simply 7. This problem beautifully demonstrates how a seemingly complex organic chemistry equation can be solved with basic stoichiometry and atom conservation.