Question

Write any two observations which support the fact that atoms are divisible

Answer 1

Atoms are divisible’ is supported by the following facts
(i)  Formation of ionic compounds is possible due to the formation of ions which involves the transfer of electrons.
(ii) Presence of isotopes for the same element is possible due to the difference in the number of neutrons.
Above observations show that atom is formed by different particles such as electrons, protons and neutrons, i.e., atom is divisible.

Answer 2

atoms are divisible because they have their subatomic particles which are further smaller than that of atom's size 
In chemical reactions their subatomic particles(electrons) take part.