Ch 2 Atoms & Molecules Flashcards
Electron
Negatively charged sub particle
Proton
Positively charged sub particles found in the nucleus
Isotopes
An element with different masses
Neutrons
uncharged subatomic particles
What makes an Isotope?
A different number of neutrons within elements
Atomic Mass Unit (amu)
Units used to measure atoms
Atomic Number
The number of protons in the nucleus
Mass Number
The total number of protons & neutrons
Anion
An ion with a negative charge
Cation
An ion with a positive charge
Average Mass Formula
Average Mass = ( Atomic Mass A * % of Isotope A) + (Atomic Mass B * % of Isotope B)
Molecular Formula vs Structural Formula
Ex: H2O vs H–O–H
Period/Series
Rows on the periodic table
Groups
Columns on the periodic table
Properties of Metals
shiny, malleable, good conductors of heat & electricity
Properties of Nonmetals
Appear dull, poor conductors of heat & electricity
Properties of Metalloids
Conducts heat & electricity relatively well, brittle, possesses properties of metals and nonmetals
Alkali Metals
Elements in group 1
ex: Li, Na, etc
Alkaline Earth Metals
Elements in group 2
Ex: Mg, Be, Ca, etc
Pnictogens
Group 15
Ex: N, P, As, etc
Chalcogens
Group 16
Ex: O, S, Se, etc
Halogens
Group 17
Ex: F, Br, I, Cl, etc
Noble Gases (Inert Gases)
Group 18
Ex: Ne, Ar, Kr, etc
Ionic Bonds
electrostatic attraction between oppositely charged ions where an element steals electrons from another element
