Periods
How are periods organised?
By the increasing atomic number
What is the atomic number of iron?
Iron is #26
What are the groups in the periodic table?
the 18 vertical columns on the periodic table also called families where elements have the same number of valence electrons and similar chemical properties
What is the symbol of potassium?
K
Why are there Periods in the table?
They correspond to energy levels
What are atomic numbers?
the number of protons in an atom's nucleus, and it uniquely identifies a chemical element
How many groups are there?
There are 18 groups also known as familys
When was the first periodic table created?
in 1869 which arranged elements by atomic mass and chemical properties, leaving gaps for undiscovered elements
How many periods are in the table?
There are seven periods on the table.
how are the atomic numbers organised?
The atomic numbers are organised by increasing from left to right and going from top to bottom
What are the groups used for?
The groups are used for organisation of the similar elements.
Who made the periodic table?
Dmitri Mendeleev created the first periodic table?