Question

If the coefficient 2 is placed in front of the product tetraiodine nonaoxide (I4O9), then, how many atoms of each element must be accounted for on the otherside of the equation?
a) 8 iodine atoms and 18 oxygen atoms
b) 4 iodine atoms and 9 oxygen atoms
c) 8 iodine atoms and 9 oxygen atoms
d) 9 iodine atoms and 4 oxygen atoms
e) 18 iodine atoms and 9 oxygen atoms

Answer 1

Answer: a) 8 iodine atoms and 18 oxygen atoms

Explanation:-

According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.

Thus if the product is $I_4O_9$ , there are 4 atoms of iodine and 9 atoms of oxygen.When a coefficient 2 is placed in front of the product tetraiodine nonaoxide $2I_4O_9$, there will be 8 atoms of iodine and 18 atoms of oxygen. Thus the reactants must also have 8 atom of iodine and 18 atoms of oxygen.

Answer 2

8 iodine atoms and 18 oxygen atoms because the law of conservation of mass holds, an equal amount must be accounted for on the other side of the chemical equation.