Chemistry Ch 3 Vocab Flashcards
Atomic Mass Unit
The average mass (in u) of the atoms of the isotopes of a given element as they occur naturally.
Periods
A horizontal row of elements in the periodic table.
Groups
A vertical column of elements in the periodic table.
Representative Elements
An element in one of the A groups in the periodic table.
Transition Elements
The elements located between Groups 2A and 3A in the periodic table.
Lanthanides
Elements 58–71.
Actinides
Elements 90–103
Alkali Metals
The Group 1A elements (except hydrogen)—lithium, sodium, potassium, rubidium, cesium, and francium.
Alkaline Earth Metals
The Group 2A elements—beryllium, magnesium, calcium, strontium, barium, and radium.
Halogens
Group 7A in the periodic table—fluorine, chlorine, bromine, iodine, and astatine.
Noble Gases
Group 8A in the periodic table—helium, neon, argon, krypton, xenon, and radon.
Metals
An element or an alloy that is a good conductor of electricity, that has a shiny surface, and that is malleable and ductile; an element that normally forms positive ions and has an oxide that is basic.
Nonmetals
A nonductile, nonmalleable, nonconducting element that tends to form negative ions (if it forms them at all) far more readily than positive ions and whose oxide is likely to show acidic properties.
Metalloids
Elements with properties that lie between those of metals and nonmetals, and that are found in the periodic table around the diagonal line running from boron (B) to astatine (At).
Cations
A positively charged ion.
