Physics Midterm Part 1 Flashcards
Matter
Anything that occupies space and has inertia.
Atom
The smallest particle of an element that has the characteristic properties of that element.
Element
A substance made up of only one kind of atom and cannot be transformed into another element
Molecule
A structure made up of two or more atoms bound together and may contain any number of atoms.
Substance
any kind of material that has a constant and definite composition.
Simple substance
elements made up of only 1 kind of atom (92 natural elements)
Compound substance
chemical union of 2 or more elements in definite proportions that can be separated by physical means.
Mixture
A physical combination of 2 or more elements in definite proportions that can be separated by physical means.
Solid
– strongest amount of attraction between atoms and molecules.
Liquid
less attraction than solids
Gas
less attraction than liquids
Plasma
Weakest attraction. These are gas ions that have had their electrons removed
Amorphous state
In this state, matter is stuck between a solid and liquid state
Sublimation
When a solid evaporates directly into a gaseous state, skipping the liquid state.
Brownian motion
All atoms and molecules vibrate or move with Brownian motion. Plasma has greatest brownish motion.
Greek model
Atoms are solid balls
Dalton model (1808)
All matter is made of atoms
•Atoms of the same element are identical
•Each element has different atoms
Thomson model (1897)
In this model, electrons (discovered by Thomson in 1897) were spread out in a sphere of positive charges, much like plumbs in plumb pudding.
Rutherford model (1910)
This model theorized that the positive charges were concentrated in a central position called the nucleus.
Bohr model (1913)
The Bohr model expands on Rutherford’s model and states that the atom is made up of 2 main parts:
Nucleus and electrons
Pauli Exclusion Principle.
There is a maximum number of electrons that can occupy each shell.
Quantum model (1926)
It states that electrons exist in probability clouds rather than be restricted to specific orbits.
n
principle quantum number. This gives the distance away from the nucleus.
I
azimuthal. This gives the amount of angular momentum, and has sub-orbitals of s, p, d, & f.
m
magnetic. This gives the amount and direction of spin.
String Theory (1970 – present)
Electrons and quarks are made up of extremely small loops of rapidly vibrating string-like matter.
