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Timeline of the Atomic Nature The story of the indivisible - Coggle…
Timeline of the Atomic Nature
The story of the indivisible
Ernest Rutherford
1.)An atom has a positive, central core, which he later called the nucleus, where most of its mass is intense.
2.)The negatively charged electrons were so tiny that they circulated the nucleus of an atom.
3.)He discovered the proton
Nuclear Model of an Atom"
It bears a resemblance to a miniature solar system, with the positively charged nucleus always at the center and the electrons revolving around the nucleus. Hence the name of the model.
Aristotle
-Proposed that all substances are composed of four elements-earth, fire, air, and water in different proportions
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Democtritus
-Proposed that everything is composed of tiny bit of indivisible matter and called it an atom
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John Dalton
-He came up with the so-called atomic theory after gathering all the findings and results of various experiments made by ancient philosophers.
His theory explains that;
1.) All matter is composed of tiny, indivisible, indestructible particles called atoms.
2.)All atoms of each element are exactly alike, but they differ from other element's atoms. The atoms of different mass and other properties.
3.)When atoms of different elements combine to form a compound, the constituent atoms are always present in the same fixed numerical ratio.
4.)A chemical reaction involves a rearrangement of atoms. No atom is created and destroy
"The Solid Sphere Model"
He pictured the atom as a solid, indestructible sphere with a mass that is like a billiard ball.
Joseph John Thomson
1.)He discovered the electrons.
2.)He proposed the presence of positive particle.
"The Raisin Bun Model"
Atoms are solid spheres made up of solid positive mass (core) with tiny negative particles embedded in the positive core, similar to the way raisins are embedded in a loaf bread
Neils Bohr
1.)He concluded that at least in some cases, energy could be emitted in discrete packages that he called quanta, not in continuous waves.
2.)He suggested that electrons could move around the nucleus without radiating energy, provided that they remained in certain restricted orbits. Moreover, he proposed that an electron could move from one orbit to another by gaining or losing one or more quanta energy
"Planetary Model of an Atoms"
The model looks like the planets revolving around the sun in certain orbits, like the electrons circling the nucleus in specific orbits.
Neils Bohr and Arnold Johannes Wilhelm Sommerferld
They introduce three refinements in Bohr's atomic model:
1.)The introduction of elliptical orbits to the Bohr Model
2.)Allowance for the orbiting motion of the electrons
3.)The consideration of relativistic mass effects
"Bohr-Sommerfeld Atomic Model"
The model is a lot like Bohr's planetary model, only that the orbits are elliptical to describe heavier elements.
Erwin Schrodinger
Explained how the electrons
move in an atom as a wave.
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James Chadwick
He discovered the neutron
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