physci
It is made up of tiny particles called atoms.
matter
Building blocks of matter. Comes from the Greek word ‘atomos’ which means indivisible or uncuttable.
atom
Two or more atoms that are held
together by attractive forces of chemical bonds.
molecules
Positively charged particle and located in the nucleus.
proton
Particle that doesn’t have any charge (neutral) and also located in the nucleus.
neutron
Negatively charged particle located in the orbits around the nucleus.
electron
He proposed that matter is composed of
fundamental particles called atoms which means
indivisible or uncuttable.
Democritus
He believed that atoms were
small, hard particles that were all made of the same
material, but formed in different shapes and sizes.
Democritus
A greek philosopher who proposed that
matter was a combination of four fundamental
elements (water, fire, wind and earth). He did not
support the idea that atom is the building blocks of
matter.
Aristotle
A scientist that used experimental method to transform Democritus’ idea into scientific theory. Proposed the Solid Sphere Model in the early 19th century.
John Dalton
He used cathode ray tube experiment discovered the subatomic particle the electron. Proposed the Plum Pudding Model in the late 19th century.
J.J Thomson
First model to propose a central, massive nucleus. Explained the behavior of positively charged alpha particles in the gold foil experiment. Introduced the Nuclear Model in the early 20th century.
Ernest Rutherford
Announced that the nucleus also contained uncharged particle, which he called the neutron.
James Chadwick
Danish physicist known for his pioneering
work in atomic structure. Proposed the Planetary
Model in the early 20th century.
Niels Bohr
He proposed the Quantum Model in the 1920s.
Erwin Schrodinger
According to this theory, atoms are tiny balls that can't be broken and are all made of the same material. This theory helped explain how different chemicals mix together and what makes them different. (atomic model)
Solid Sphere Model
According to this theory, atoms are like plum pudding, with tiny positive charges scattered throughout a cloud of negative electrons. (atomic model)
Plum Pudding Model
According to this model, atom is mostly an empty space with a small positively charged dense core called nucleus. It explains why particles can pass through or bounce off atoms. (atomic model)
Nuclear model
According to this theory, electrons orbit the nucleus of an atom in specific energy levels or shells. The electrons orbit around the nucleus similar to how planets orbit around the sun. (atomic model)
Planetary Model
According to this theory, electrons exist as a probable wave-like pattern around the nucleus, not in a specific orbit. (atomic model)
Quantum model