Periodic table Flashcards
How did Mendeleev present his periodic table?
He organised his periodic table by looking at the masses and identified patterns within the properties of the elements that he put into his table. because of this he was able identify gaps and predict their properties of the elements that would later be discovered
Who is Mendeleev ?
The first person to put together the periodic table that is similar to the one we use today.
presented his table in 1869
How is Mendeleev’s periodic table different to the one we have now ?
The current one is organised by atomic numbers and includes noble gases where as Mendeleev’s one was organised by mass
where are the lighter elements
at the top
Which elements are at the bottom
the heavy ones
Problems of Mendeleev’s table
Few elements ended up in wrong column because of atomic mass as there were isotopes present.
What are the rows going from left to right are
Periods
elements in the same periods all share the same number of energy shells
Whats the link between periods ?
elements in the first period have one shell and as we go down the shells increase by 1
What are the columns going up to down called
groups
what do elements in the same group all have in common
elements in the same group all have the same number of outer electrons
What is electronic configuration
the number of electrons on each shell
(2.8.2)
Which side are the non-metals found ?
Right
What side are the metals found ?
Left
Where are the noble gases found and what are they?
Group 0
They are the first group on the right
They have full outer electron shells
John Newlands
John Newlands was the first chemist to devise a periodic table.
He ordered his table by the weight of the element.
However, the table was incomplete, and some elements were place in inappropriate groups.
