Answer:
John Dalton described the atoms based on there chemical and physical properties of which some were disproved later.
Explanation:
John Dalton described the atoms as
- Atoms are the smallest indivisible particles of matter.
- Atoms can neither be created nor destroyed.
- All atoms of the same element are identical by mass and size.
- Atoms of the different element have different mass and size.
- Atoms combined to form a compound and they do so in simply whole number ratio.
By using flame test we can identify the elements because colors which are given by elements with flame test are unique.
During the flame test, the electrons of the atom which are in ground state absorb energy and go to upper level. This is called electron excitation. Excited electrons are unstable. Hence, they come back to the ground state by emitting the energy as photons. If that released energy has a frequency which belongs to visual light, then that wave gives a color.
Answer:
Thomson's experiments with cathode ray tubes showed that all atoms contain tiny negatively charged subatomic particles or electrons. Thomson's plum pudding model of the atom had negatively-charged electrons embedded within a positively-charged "soup.
Answer:
first conclusion was that the whole world is made up of only 4 elements but as the time passed more elements were discovered... if the world would not contain more elements... you wouldn't be alive.
