Answer:
The correct answer to you your question is Potassium
Explanation:
Potassium is the most reactive
Intermolecular force for solids is high. Whereas low in gases. The smell of agarbatti spreads immediately because the molecules of air diffuses very fastly.
The law of conservation of mass states that the mass of a system must remain constant everytime, it can neither be created or destroyed. This means the number of atoms of each element on reactant side must equal the number of atoms of each element on product side.
First we figure out the chemical formula for each compound by taking advantage of oxidation states which are able to tell us whether an element will lose or gain an electron
Strontium hydroxide?
Sr is an alkaline earth metal which has 2 valence electrons that when both are lost it has an oxidation state of +2. Since we know the hydroxide ion has a charge of -1,
, Then two
are needed to form compound, hence we have 
zirconium (I) perchlorate?
The oxidation state of zirconium is +1 since it is stated that we have zirconium(I). Converserly, perchlorate has a -1 charge which further proves that zirconium has a +1 oxidation state
The product would have a strontium diperchlorate because we know from earlier that Sr has a +2 oxidation state, and we would also have ZrOH because Zr has a +1 oxidation state and
has a -1 charge
The unbalanced equation with all chemicals formulas would be

Using the law of conservation of mass, it is clear that there is 1 molecule of
on reactant side as compared to 2 molecules of
on product side. On the other hand, the are 2 molecules of
on reactant side and 1 molecule of
on product side. To balance we add a coefficient of 2 on
and a coefficient of 2 on ZrOH,
.
<span>The key difference between Mendeleev and modern periodic table is that Mendeleev’s periodic table was based on the increasing atomic masses while the modern periodic table is based on the increasing atomic numbers. Let us see here what is Mendeleev periodic table and what is modern periodic table, and then compare both to understand the difference between both periodic tables. Mendeleev is the pioneer of the modern periodic table, though a numerous number of changes had been made to the old version of the periodic table. Both of these attempts are equally important to the scientific community; because without an invention of the periodic relationship in elements, the modern developments in Science would not reach a development era as today. Before the invention of Mendeleev’s classification, there were several attempts made by several chemists, but their periodic laws were inadequate to apply for all the elements. The modern periodic table is so advantageous for the development in the Science.</span>