Zusammenfassung der Ressource
Atomic Structure
- Demoritus
- Claimed that matter could not be
divided into smaller pieces forever
- John Dalton
- Thought atoms are tiny solid ball,
came up with atomic theory
- In 1805, John Dalton published his
atomic theory
- All matter is made of tiny particles
called atoms
- Atoms are tiny hard spheres that cannot
be broken down into smaller parts
- Atoms cannot be
created or destroyed
- Atoms in an element always
have the equal amount of
protons and elctrons
- J.J Thomson
- Discovered electrons and also discovered
atoms are made from positive and negative
charged electrons
- Rutherford
- Discovered protons and nucleus. He called
positive particles "protons" and the center
of atoms the nucleus. He showed that
atoms have positive particles in the center
and mostly empty space.
- Niels Bohr
- Improved on Rutherford model and
proposed that electrons move
around the track around nucleus
known as the shell.
- Chadwick
- Discovered particles with no
charge and called it "Neutrons".
Neutrons are also found in the
nucleus.
- The new atomic model has
electrons moving around the
nucleus in a cloud.
- The overall diameter of an atom can be 100,000 times
- Atoms are made up of electrons
together with heavier subatomic
particle called protons, electron and
neutrons, these particles have very,
very small masses and electric charges
- The actual mass of a proton is 1.67*10 g
- It is impossible to know where an electron is at
any given time