Atomic Structures Flashcards
What’s an atom
Smallest part of an element that can exist
Daltons atom model
Atoms are tiny solid spheres that are indivisible
Element
Substance made from one type of atom
Compound
Made from two or more types of atoms chemically bonded together in fixed proportions
Molecule
Two or more atoms chemically bonded together
Plum pudding model
Sphere of positive charge with negative electrons imbedded in it
Unexpected discovery alpha particles
Some alpha particles were deflected straight back
Why did most particles pass straight through
Most of the atom is empty space
What did alpha particle experiment show about atomic structure
Most of atoms mass an positive chnarge is concentrated into a tiny space
Nuclear model
Dense positively charged nucleus with electrons randomly orbiting
What did Niels Bohr discover
Electrons orbit in fixed energy levels or shells
What did james Chadwick discover
Uncharged particle called the neutron
Where in the atom are protons and neutrons
Nucleus
Relative masses
Electron 0
Proton 1
Neutron 1
Relative charges
Electron -1
Proton +1
Neutron 0
