Atoms

1) Atoms should be indissoluble the littlest conceivable unit of matter.

2) PROUT'S HYPOTHESIS: In 1815, Prout found that nuclear weights of fog of the components were basic products of the nuclear weight of hydrogen.He, in this manner, suggested that each component is comprised of hydrogen atoms.This theory was disposed of when certain components were found to have fragmentary nuclear weights.

3) IMPACT PARAMETER AND ANGLE OF SCATTERING: Impact parameter is characterized as the opposite separation of the speed vector of a α-molecule from the focal point of the core (when the α-molecule is far from the iota).

4) CONTINUOUS SPECTRUM: It comprise of consistent wavelength inside a distinct extent as on account of noticeable light.It is likewise called the white range.

5) SHARP LINE SPECTRUM: It comprise of gatherings of sharp lines of distinct wavelength, superimposed over the consistent range.

6) EXCITED STATE: The procedure in which electron of a particle moves to a circle of more prominent vitality in the wake of retaining some vitality is called e excitation of the molecule and the itself is said to in the energized state.

7) IONIZED STATE: The procedure in which an electron of the particle is legitimately expelled from it abandoning a net positive charge on it is known as the ionization of the molecule and this state is called ionized state.

8) ATOMIC SPECTRA: The branch of material science that arrangements with the examination of the wavelengths and intensities of e.m.radiation radiated or consumed by iotas is called nuclear spectra.

9) THOMSON MODEL OF ATOM: Sir J.J. Thomson contemplated the marvel of release of power through gasses at low weights, alongside the nature and properties of cathode beams and positive beams. On the premise of his examinations, he proposed in 1907 what is currently called Thomson's plum-pudding model of a molecule. As per this model, a particle comprises of circle of span of the request of 10-10 m. The particles in charge of the mass of the molecule convey positive charge and are circulated consistently over the sphere.The adversely charged particles, called electrons, are inserted inside the iota .Every molecule is electrically impartial so that the aggregate positive charge on a molecule is equivalent to aggregate negative charge on it.

Thomson's model couldn't clarify:

a) The emanation of phantom lines from the molecules,

b) The substantial edge scrambling of α-particles by dainty metal foils.

10) Dalton's Atomic Theory: John Dalton, in 1808, set forward his hypothesis, as per which:

i) All concoction components are made out of small particles, called iotas. these particles can't be subdivided further and

ii) Atoms of a specific component take after each other while iotas of various components contrast from each other.

No one genuinely scrutinized Dalton's hypothesis until about the start of the twentieth century.