The periodic table of elements
Group (family) properties
18 of these on the periodic table number from left to right atomic numbers and atomic masses increase as you move from the top down. I love this of elements in the same group have the same number of electrons in the outer orbitals or levels of their's. They're also known as valance electrons
Elements
A pure substance that is made up of one kind of Adam that cannot be broken down into simpler substances by physical or chemical means. 90 occur naturally on. 25 were made by scientists.
Periodic table of elements
A table of the elements, arranged by atomic number, that shows the patterns in their properties based on the periodic law
Mendeleev's predictions
Although his periodic table of elements are missing elements or gaps he was able to predict the characteristics of these missing elements because of periodic law
Physical properties of metalloids
Have properties of both metals and nonmetals
Metals
Are Atoms with few electrons in their outer energy level
Metalloids
Atoms with about one half complete outer energy
Nonmetals
Atoms with full or almost full outer energy levels
Metalloids
Border zigzag line or staircase on the periodic table
Physical properties of metals
Ductile, good conductors, malleable, Shiny, most are solid at room temperature
Chemical properties of metals
Has to you electrons in their outer energy levels suss lose electrons easily
Henry Moseley
In 1914 his work lead to a revision of the periodic table by rearranging the elements by their atomic number. He concluded that the number of photons in and Atom is its atomic number
Dmitri Mendeleev
In the 1860s he devised a periodic table with elements were ordered by their atomic masses. He did this by grouping elements together according to their similarities.
Periodic law
Mendeleev was able to predict the characteristics of missing elements because of this
Chemical properties of metalloids
Most Atomd have about half complete set of electrons in outer level
Chemical properties of nonmetals
Most have fall outer energy levels thus they tend to gain electrons some have completely full outer level
Nonmetals
Most sound to the right of the zigzag line or staircase on the periodic table
Physical properties of nonmetals
Not ductile or malleable not shiney and poor conductors most are solid but some are gas at room temperature
Periodic
Occurs at regular or at least generally predictable intervals
Periodic law
Physical and chemical properties of the elements are periodic functions of their atomic numbers
Period (row) properties
Seven. On a periodic table number from the top down. Atomic numbers and atomic masses increase as you move from the left to the right in the period. All atoms of the outlets in the same period have the same number of Orbitzal levels. All Adams of the element in a specific period have that respective number of orbital or levels
Metals
Sounds on the last of the zigzag lines staircase on the periodic table the exception is hydrogen only
How to calculate the number of protons neutrons and electrons while using the periodic table of elements
The number of protons is the same as the atomic number subtract the atomic weight and it's haven't number to find the number of neutrons. The number of electrons is the same as the protons unless it is an ion.
Mosley and medeeleev
The two scientists who contributed to the creation and revision of the periodic table
Metals, metalloids, nonmetals
Three classes of elements
Elements in a group
Usually have similar physical and chemical properties
