History
What was the name of a Greek philosopher that had the idea that everything was made of elements?
Democritus
The periodic is a chart that shows ___...
all of the known chemical elements in one place.
Periodic trends are ____ that are present in the periodic table that show different aspects of a certain elements.
patterns
"When elements are arranged in order of increasing atomic number, patterns emerged."
Periodic Law
How many known elements are there?
118
The major periodic trends are electronegativity, ionization energy, electron affinity, atomic radius, melting/boiling point, and _______.
density.
In 1913 ________ were discovered, which allowed us to rearrange the table to its current state.
protons
The periodic table shows us how many ___, so that elements that are similar in properties, line up.
protons,electrons and atomic mass,
Periodic trends, come from the arrangement of the periodic table, provide chemists with an invaluable tool to quickly predict an element's _____.
properties.
He was a Russian chemist and he had published the first widely recognized periodic table.
Dmitri Mendeleev
We use the numbers of protons in the nucleus to identify the element, this is called the
atomic number
what are one of the major periodic trends?
ionization energy or electronegativity or atomic radius
In 1789, Antoine __________ made the earliest attempt to classify the elements.
Lavoisier
The periodic table is structured into ___ and ____
periods and groups
These trends exist because of the _______ within their respective group families or periods, and because of the periodic nature of the elements.
similar atomic structure of the elements