Atoms Elements and The Periodic table Flashcards
Lost some facts about elements
They cannot be broken down into anything simpler by chemical means
Each element has it own symbol
Elements are made up of one type of atom
The atomic structure of an elm any deter mains it position in the periodic table
What is an element
Element are basic building blocks
of matter
Describe the features of an atom
Each atom contains a small, positively charged nucleus with an orbiting cloud of light negatively charged electrons
What is the nucleus made up of
Protons - positively charged
Neutrons - negatively charged
How do you know what the number of protons are
It is the atomic number and remember each element has a different atomic number
What is the mass of an element called
Relative atomic mass
What contains the most mass of an atom
The nucleus
Describe what the periodic table is
A table in which all the known element are arranged in a logical way that allows chemists to predict the properties of each individual element
How is the periodic table set out
The rows of the periodic table are called periods
The Columns are called groups
Who developed the periodic table
Dmitri Mendleev in 1869
What did Dmitri Mendeleev notice about the periodic table
The element were arranged in order of relative atomic mass and the promotors showed recurring patterns
There appeared to be gaps that he conclude to be for elements that had not yet been discovered
He predicted the properties of the elements that had not been discovered
The element are now arranged in order of atomic number not atomic mass
What are the elements in group 8 sometimes referred as
The noble gases
How can we tell how many shells an atom has using the the periodic table
The number of shells depends on the row its in
