Atomic Structure Snd The Periodic Table Flashcards
What is the structure of an atom
The nucleus is the man part of the atom and it contains protons and neutrons
The electrons orbit the atoms in shells
How to work out the number of electrons
It is equal to the number of protons so the overall charge of the atom is 0
What are the electron shell rules
The inner shells are filled first
There’s a maximum of 2 electrons int he first shell 8 in the second and 8 in the third
What are Elements
They contain only one type of atom
Each element has a unique number of protons
What are isotopes
Different atomic forms of the same element which have the same number of protons but different numbers of neutrons
How to work out relative atomic mass
Multiply the mass of each isotope by its abundance
Add them together
Divide by the sum of the relative abundances
What did Mendeleev’s periodic table show us
He placed chemicals with similar chemical properties in vertical rows and had to leave gaps so that showed there were still elements to be discovered
It could predict the properties of the undercovered elements
What are the periods of the periodic table for
They are the rows
The period number is the same as the amount of shells the atom has
What dot he groups of the periodic table show us
They are the columns
Elements in the same group have similar properties because they have the same amount of electrons in their outer shells
The group number is always equal to the amount of electrons in the outer shell except the group 0 elements have 8 outer electrons
