Chapter 4 Atoms and the Periodic Table Flashcards
Nucleus
The very center of an atom that is really small and dense and has a positive charge
Proton
Positive charged particles
Neutron
Neutral charge
Electron
Negative charged particle
Orbital
Part of an atom where the electrons are most likely to be found
Valence electrons
Electron that is found on the outermost energy level part of an atom
Periodic law
States that when element are put not a certain order, the similarities in their properties will begin to form into a regular pattern
Period
Each individual horizontal row that occurs on the periodic table
Group
Vertical lines that are on the periodic table
Ion
An atom or group of atoms that either lose or gain more electrons and have a negative or positive charge
Atomic number
Indicates how many protons are in a single atom
Mass number
Protons and neutrons added together
Isotope
An atom of the same elements with a different number of neutrons but the same number of protons
Atomic mass unit (amu)
Unit used to describe the mass of an atom or molecule
Average atomic mass
The average weight of an element
Metal
Shiny solids that are stretched and shaped on the periodic table
Nonmetal
Found on the right side of the periodic table and can be a solid liquid or gas
Semiconductor
Metalloids
Alkali metal
Soft, shiny and react violently with water; found in Group 1
Alkaline-Earth Metal
Elements with 2 valence electrons
Transition metal
Metals that lose electrons to form positive ions
Halogen
Found in a Group 17 on periodic table
Noble gas
Found in Group 18 on the periodic table and are unreactive
Mole
Collection of a very large number of particles
Avoagdro’s constant
6.002*10^23/mol. The number of particles in one mole
Molar mass
Mass in grams of one mole in a substance
Conversion factor
A ratio used to convert one unit to another
