It's because the Law of Conservation of Mass WILL NOT be followed if,
from SO2 and water, sulfuric acid is formed. Making a balanced chemical
reaction is not possible, no matter what you do. To obtain or make sulfuric acid, SO2
still needs to be oxidized further to SO3.
Answer: a) 
b) 1 mole of 
is produced.
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.
The skeletal equation is:
The balanced equation will be:
Thus the coefficients are 2, 3 , 10 , 4 , 3 , 2 and 5.
b) Oxidation: 
Reduction: 
Net reaction: 
When 1 mole of 
is produced, 1 mole of is produced.
there's no question on here
Dimitri Mendeleev was the first to put elements together on a table. He knew there were elements missing but he noticed a trend in some of the elements known at the time. Sodium, Lithium and other alkali metals all have the same properties so he put them under the same column and created other columns with similar attributes (Halogens, Noble gases, Alkaline earth metals). Over the years, new elements were discovered and put into the rough outline that Mendeleev created.
I hope that is about what you wanted.
