John Dalton worked in the first years of the 19th century.
Dalton proposed it in Dalton's atomic theory (i think)
Atoms are made up of smaller particles.
John Dalton
Atoms are made up of the smallest form of matter
Atoms are made up of the smallest form of matter
Dalton came up with that theory. It was proven wrong, though.
All the atoms in elements are not a like
John dalton
the element carbon is made up of carbon and nitrogen
The first person to develop the first model of the atom in 1803 was John Dalton.
All the atoms in elements are not a like.
It depends. If you mean just any old atomic theory, credit usually goes to either Democritus or his mentor Leucippus. However, if you mean an atomic theory that wasn't totally blowing smoke out their nether regions, was backed up by actual experimental data, and at least resembled the truth in certain ways if you squinted hard enough, I'd say John Dalton is probably your guy.