Ch. 6 The Periodic Table And Periodic Table Flashcards
The first periodic table was developed by ?
Dmitri Mendeleev
- the elements were arranged according to increasing atomic mass
- one important result of this table was that the existence and properties of undiscovered elements could be predicted
The law of octaves
The properties of the elements repeated every eight elements
- did not work for all known elements and was not generally accepted
The elements in the modern periodic table are arranged according to increasing
Atomic number
- credited to Henry Moseley
- arrangement is based on number of protons in the nucleus of an atom of the element
Periodic law
States that when elements are arranged according to increasing atomic number, there is a periodic repetition of their chemical and physical properties
Metals
Elements that are shiny and conduct electricity
Group
A column on the periodic table
Period
A row on the periodic table
Representative elements
Group A elements
Transition elements
Group B elements
There are ____ main classifications of elements
3
More than 3-4ths of the elements in the periodic table are
Metals
True or false ?
Group 1A elements except for hydrogen are known as the alkali metals
True
Group _____ elements are the alkaline earth metals
Group 2A
True or false ?
Group 7A elements are highly reactive non metals known as halogens
True
Group 8A elements are very u reactive elements known as
Noble gasses
