Question

Which chemical reaction model is flawed?

Answer 1

The equation in option A appears to be flawed.

The left hand side of the first equation contains eight carbon atoms whereas the right hand side contains only four. This equation is thus not properly balanced.

Answer 2

Answer: Option (A) is the correct answer.

Explanation:

A balanced equation is defined as the equation where number of atoms of the reactant equal to the number of atoms of the product.  

This also means that mass of the reactants is equal to the mass of products in a chemical equation.

For example, $2Fe + 3Cl_{2} \rightarrow 2FeCl_{3}$

But when the number of moles of reactants is not equal to the number of moles of products then the reaction equation is not balanced.

For example, $4C_{2} + S_{8} \rightarrow 4CS_{2}$

Here, the moles of carbon atom are not equal on both reactant and product side. Hence, this reaction equation is not balanced.

Thus, we can conclude that out of the given options $4C_{2} + S_{8} \rightarrow 4CS_{2}$, this chemical reaction model is flawed.