p1.1-The Particle Model Flashcards
p1.1.1-What was Daltons model?
He thought everything was made out of atoms and that the atom is a small indestructible sphere.
All atoms in an element are the same. The atoms in one element are different from atoms in another.
p1.1.1-What was Thomsons model?
He found out cathode rays are made up of very small particles which he called an electron which must have been inside an atom. An atom contains negative electrons and overall atoms have no electric charge as they are neutral.
p1.1.1-What was Thomsons new model?
The plum-pudding model of the atom where the atom is thought to consist of positive mass with negative electrons embedded in it.
p1.1.2-What was Rutherfords experiment?
Rutherford fired alpha particles at a piece of gold, but was surprised as a few bounced back and this could not be explained with the plum-pudding model. Almost all of the mass of an atom is in its nucleus which is why the particles bounced back.
p1.1.2-What was the Rutherford model?
Rutherford suggested that an atom is made up of a tiny positively charged nucleus with electrons around the outside. Later, scientists discovered that the nucleus was made up of two different types of particles in protons and neutrons.
p1.1.2-What was the Bohr Model?
Niels Bohr suggested that electrons can only move in fixed orbits called electron shells around the nucleus.
p1.1.2-How did the Model of the Atom develop?
1870s-Dalton Model
1897, 1904-Thomson Model
1899-Rutherford Model
1913-Bohr Model
p1.1.2-How big are atoms?
An atom is 1x10^-10m in diameter.
