Science
Development Of The Periodic Table
It is approximately 100 elements.
Sub-Atomic Discoveries
The discovery allowed scientists to work out that elements with the same numbers of electrons in their outer shell had similar chemical properties.
The discovery of protons allowed scientists to order the elements in the Periodic Table by their atomic numbers.
The discovery of protons allowed scientists to order the elements in the Periodic Table by their atomic number.
Group 0
It has changed a lot over time as scientists have organised the elements differently.
The first list of elements,Mendeleev's Periodic Table,and the modern Periodic Table have a number of differences in how they list the discovered elements.
Elements in Group 0 are called the noble gases.
Noble gases have the following properties:
Full outer shells,so do not to loose or gain electrons.
Very unreactive (inert)so exist as single atoms as they do not bound to form molecules.
Boiling points that increases down the group.
Group 1 elements and Group 1 properties
Group 1 elements react with oxygen,chlorine,and water,for example:
Lithium+Oxygen->Lithium Oxide
Lithium+Chlorine->Lithium Chloride
Lithium+Water->Lithium Hydroxide+Hydrogen