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21 terms

Atomic Model

Memorize Rutherford's, Dalton's, Schrodinger's, and Thompson's model of the atom.
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Dalton's Atomic Model
All matter is made up of atoms (small, indivisible, indestructible, fundamental particles) - PARTICLE THEORY OF MATTER
Dalton's Atomic Model
Atoms can neither be created nor destroyed (they persist unchanged for all eternity)
Dalton's Atomic Model
Atoms of a particular element are alike (in size, mass, and properties)
Dalton's Atomic Model
Atoms of different elements are different from one another (different sizes, masses, and properties)
Dalton's Atomic Model
A chemical reaction involves either the union or the separation of individual atoms.
Dalton's Atomic Model
Ball and hook model
The Law of conservation of matter and the Law of definite composition (in a pure chemical compound)
Evidence Dalton based his model on
Thompson's Atomic Model
Plum pudding model - positive pudding sprinkled with negative electrons
Thompson's Atomic Model
electrons are small, negatively charged particles
Atoms behave as if they are electrically neutral
Evidence for Thompson's model
Helped update the image of what an atom looks like—not a ball and hook and Discovered the first subatomic particle (the electron) - atoms are not the fundamental particles of matter
How Thompson's model improved on Dalton's
Rutherford's Atomic Model
Atom is mostly empty space with a tiny, dense nucleus
Rutherford's Atomic Model
Electrons move around nucleus in some fashion
He shot alpha particles at gold foil and they mostly went through but some were deflected in different directions because they happened to hit the nucleus of a gold atom
Experiment Rutherford based his model on
Rutherford shoots alpha particles at gold foil and they mostly went through but some were deflected in different directions because they happened to hit the nucleus of a gold atom
The Alpha-Particle Experiment
Discovered the nucleus - there must be a center of positive energy rather than positive pudding
How did Rutherford improve on Thompson's model?
Electrons orbit the nucleus in shells determined by fixed energies (quantized)—can jump levels when absorbing or emitting energy
Bohr's Atomic Model
Electrons at lower energies are more tightly bound to the nucleus, making the atom more stable
Bohr's Atomic Model
Who's work was Bohr's model based on?
Max Planck
How did Bohr improve on Thompson's Model?
He provided a more accurate image of what an atom looks like and how it works and explained how electrons move in the atom
Modern Quantum Mechanical Model of the Atom
Uncertainty principal - electrons move and are likely to be within an area at any given time - orbitals