Elements Metal Properties And Atomic Number
This chapter is about elements, metal properties.
What did John Newlands do?
arranged the first 16 elements in two rows of eight. He noticed that each column had similar chemical properties
What is the law of octaves?
repeating properties with eight elements
Dobereiner?
triad of elements
Who is Dmitri Mendeleeve?
Father of the periodic table invented the first periodic system, arranged 63 known elements according to their increasing mass
Who is Henry Moseley?
established the physical basis for the periodic arrangement of elements by atomic numbers, studied X-Ray Analysis of elements that produced spectral lines – new technology, These lines correlated Groupings by Atomic number not Atomic mass
What is the modern Periodic law?
“physical and chemical properties of elements are a function of the elements Atomic number”
Who is Seaborg?
last to alter table – moved La dna dc below table to 106
What are two qualities of valence electrons?
determine chemical properties of elements, are the electrons in the highest (numerical) principle energy level
IA?
Alkali Metals
IIA?
Alkaline earth metals
IIIA?
Boron Group
IVA?
Carbon Group
VA?
Nitrogen Group
VIA?
Chalcogen or Oxygen Group
VIIA?
Halogen Group
VIIIA?
Inert or Noble Gases Group
What are Inert gases?
S2p6 full S and P valence electron (8) except He without only 1S2
What are Semimetals?
have both properties: B, Si, Ge, As, Sb, Te Also called metalloids
What are metals?
only S1 or S2 outer valence electron – held very loosely, easily lost to make “t” cations electron are good conductors move easily into the conduction band, malleable, ductile due to loose electron
IA alkali metals are what?
the most reactive metal group on the table
Metal trend?
increases from right to left (Period) and top to bottom (Group) Fr – most reactive metal on the table metallic
nonmetals?
S2P6 valence electron held tightly, filling outer p, more protons in period have a stronger hold on electron
Trend?
most reactive nonmetal is F
Insulators?
do not conduct Gases brittle
What group do elements do Ca, Be, and Mg belong to?
Alkaline Earth Metals
What group of elements easily gains one valence electron?
Halogens
What category do most of the elements of the periodic table fall under?
metals
What is the term for the energy released when an atom gains an electron
electron affinity
What are elements 90-103 called?
radioactive metals
What are elements in the first group of the periodic table called?
Alkali
What atomic property affects periodic trends down a group in the periodic table?
ionization
What two atomic properties have an increasing trend as you move across a period?
electronegativity, Atomic number
Which group of elements has a very high ionization energies and very low electron affinities?
IVA
How many valence electrons does a fluorine atom have?
7
What is an example of an alloy?
steel
How was Moseley’s arrangement of the elements in the periodic table different from Mendeleev’s?
Moseley grouped it by atomic number
What did the gaps on Mendeleev’s periodic table represent?
They were for elements that weren’t discovered yet
Why was Mendeleev’s periodic table accepted by most chemists?
It was organized and easy to use
What determines the horizontal arrangement of the periodic table?
characteristics
Why is barium, Ba, placed in Group 2 and in period 6?
Because it has 6 valence electrons
Why is hydrogen in a class by itself?
because it doesn’t have the same metallic properties