Democritus (Greek: Δημόκριτος, Dēmokritos, "chosen of the people") lived from ca. 460 BC to ca. 370 BC, so roughly it must have been about 400 BC, certainly not 250 BC as stated in other answers up till now.
DEMOCRITIS!
This is believed to have originated with the Greek Philosopher Leucippus of Miletus and his student Democritis of Adbera in the 5th Century BC
He didn't have one. His only name was Democritis, which meant "chosen of the people".
around 430 B.C.
Dalton, who got the idea from Democritis. Dalton turned this idea into a scientific theory which was All elements are composed of indivisible particles called atoms, Atoms of all elements are different from one another, Atoms of elements can mix together in whole number ratios to form compunds, and Chemical reactions occur as a result of when atoms are separated, joined, or rearranged.
No he DIDN'T
About 114 or 118.
i think 1956 but not sure
ji;
Hisname was Democritus, and he came up with the word "atom," which is Greek for indivisible.
helped discover atoms an atomic theory
The nucleus was discovered in 1899.