## Quantum Mechanics

Quantum mechanics is a branch of physics that deals with atomic and sub-atomic particles.

### Science Branches

Science
Natural Science
Physical Science
Physics
Modern Physics
Quantum Physics
Quantum Mechanics

## Atomic Properties

• Atoms (see periodic table) are made up of electrons, neutrons, and protons called subatomic particles.
• Atoms can be joined togeather to create molecules.
• Atoms have both nutrons and protons in the necleus.
• A neutral atom or normal atom has an equal number of electrons (-) and nuetrons (+).
• An ion has an unequal number of electrons and nuetrons (more or less electrons).  Positive charge if more protons than electrons (missing electrons).  Negative charge if less protons than electrons (extra electrons).
• Atoms have an equal number of protons and electrons since the electrical charge has to balance out.
• Atomic weight is the total number of particles in an atom's nucleus or specifically the average weight of naturally occuring isatobes of an element related to the mass.
• The atomic number or proton number is the number of protons in an atom of the element.
• All atoms have neutrons except for hydrogen atoms.
• Electrons have a negative electrical charge.
• Electrons orbit the neucleus of an atom.
• Electrons are 1,800 times smaller than neutrons and protons.
• Neutrons have no charge.
• To find the number of nuetrons if you know the isatobe of the atom, subtract the number of protons from the mass number.
• Isatobes are created when you change the normal number of nuetrons in an atom.
• Protrons have a positive electrical charge.
• One proton is about 1,835 times more massive than an electron.
• Protrons and newtrons normally stick togeather except in radioactive decay when thay may be knocked out.

## Quantum mechanics Glossary

### A

• Absolute Pressure  -  A pressure at absolute zero can only exist in a total vacuum and any pressure above this is called absolute pressure.

### Z

Display #
Title
Amount of Substance
Atomic Mass
Cation
Electron
Ion