Question

According to modern atomic theory:
A.Atom is divisible
B.It consists of neutrons, protons and electrons
C.Atoms of elements are alike in all respect
D.Option A and B are correct

Answer 1

Hint: Before answering this question, we should know that due to the many flaws in Dalton’s atomic theory, Scientists started to research more and perform different experiments to explain the ‘Atom’, its structure, and properties. This resulted in the birth of a modern atomic theory.

Complete answer:
The modern atomic theory highlighted the flaws in Dalton’s atomic theory that are :
Atoms are not indivisible, They are composed of subatomic particles.
There can be atoms of the same element that are not the same/identical. They are known as isotopes.
Atoms are not always combined in small numbers. A large number of atoms are combined to form a molecule in polymers.
Atoms can be destroyed by atom bombs/fission.
Subatomic parts take place in some reactions like radioactive decay.
The modern atomic theory gives a brief explanation of the atom and its behaviour.
Electrons, protons, and neutrons are the subatomic particles of the atom.
Electrons are found in the orbitals revolving around the nucleus whereas the protons and neutrons form the core of an atom.
Sub energy levels are there in the energy levels.
Electrons occupy the orbitals which are the energy levels that show the energy of a certain electron.
Atoms that are of the same element can have a different number of electrons which are called ions and a different number of neutrons that are isotopes.
Same elements or different elements can form compounds.
When elements are seen together, they have various properties that can vary periodically.

So, Option (D) “Option A and B are correct” is correct.

Note:
The discovery of Dalton is well-appreciated because there was no modern laboratory, no well-equipment were present but still he was able to build up a theory on Atoms that are not visible to our eyes. This made a path for the development of Modern atomic theory which gave us all theories and explanations regarding the atom.