Answer:
Oxygen atoms
Step-by-step explanation:
The law of conservation of mass states that matter can neither can be created nor destroyed. This means that during a chemical reaction, the number of a particular atom in the reactant must be equal to the total number of the same atom in the product.
It can thus be deduced that the oxygen atoms in the equation given in the question violates this law as the total oxygen atoms in the reactant side is 20 while those in the product side is 26. Hence, the equation is not balanced.
The balanced chemical equation is
2C₄H₁₀ + 13O₂ ⇒ 8CO₂ + 10H₂O
Here, the number of oxygen atoms on both sides is 26