True or False
There are 2 main classifications of elements
More than 3/4 of the elements in the periodic table are nonmetals
Group 1 elements (except for Hydrogen) are known as Alakli Metals
Group 13 elements are known as alkaline earth metals.
Group 17 elements are very highly reactive nonmetals known as halogens
group 18 elements are known as transition metals.
Metalloids have properties of both metals and inner transition metals
a column on the periodic table
a row on the periodic table
elements in groups 1, 2 , 13 to 18
elements that are shiny and conduct electricity
elements in groups 3-12
atomic radii cannot be measured directly because the electron cloud surrounding the nucleus does not have a clearly defined
A ____ is an atom, or bonded group of atoms that has a positive or negative charge
elements in the same group have the same number of
most of the elements in groups 16-18 are classified as
wha is the trends in atomic radii as you move from left to right across a period?
shielding by inner electrons
the trend in the atmic radii as you move down the group 1 elements is due to
How many electrons does an atom need in its outer level to be the most stable?
A German chemist that observed that several elements with similar properties could be classified into sets of 3 Triads
Found that when he arranged elements in increasing atomic mass the properties would be similar ever 8th element.
In 1865 there were ____ known elements.
_________ is credited as the father of the periodic table because he was the first to publish and demonstrate his table
He arranged the elements by increasing atomic mass.
He placed elements with similar reactivity and properties in columns.
He also left gaps to indicate that an undiscovered element should be there.
_______________ an English chemist developed the concept of atomic number.
________________ When elements are arranged in order of increasing atomic number, their physical and chemical properties show a periodic pattern.
Groups or Families
_______________ the elements with similar properties and are aligned in vertical columns (18)
___________ the horizontal rows (7)
Traditional or Roman
____________ Roman numerals and letters
_________ numbers and letters
_______ numbers 1-18
(group 1A except hydrogen) -
Found in nature in compounds
Alkaline Earth Metals
(B groups) -
Found in the middle of the periodic table
Innertransition Metals (2 pulled out rows)
Very reactive nonmetals
Are often found in compounds (salts)
Very unreactive nonmetals
They seldom form compounds
group 1A and 2A and helium
group 3A to group 8A
transition metals, the middle of the periodic table. It contains a few exceptions.
innertransition metals, the 2 rows under the table. The electrons of the f sublevel do not fill their orbitals in a predictable manner.
Atoms can gain or lose electrons to form a ___
________________-atoms tend to gain, lose, or share electrons in order to acquire a full set (8) of valence electrons.
Ionization energies ________ as you move down a group
Ionization energies _________ as you move from left to right across a period.
Successive ionization energy
The energy required to remove electrons beyond the 1st electron.
The energy change that occurs when an atom gains an extra electron
A measure of the ability of an atom in a chemical compound to attract electrons.
Increase as you move from left to right across a period. Except Noble gases
Decrease as you move down a group.
The most electronegative element is ________
The Law of Octaves did not work for every known element. True/ False
The first periodic Table is creddited to