Atoms, Elements and compounds Flashcards
Element
Are simple substances that cannot be split into smaller ones by chemical reactions.
Atom (Definition)
Atoms are the smallest part of an element that can exist.
What are the 3 subatomic particles that an atom is made up of?
Protons
Neutrons
Electrons
Molecules
Small group of atoms covalently bonded
Atomic Number
The number of protons an element contains in its nucleus.
Mass number
The number of protons plus the number of neutrons an element contains in its nucleus.
Isotope
Atoms of the same element that have different number of neutrons.
Ion
An ion is a charged atom or group of atoms.
It has gained or losing of electrons.
What is a group in the periodic table
They react in similar ways because their atoms have the same number of electrons.
What is a period in the periodic table
A period is one of the horizontal rows, whose elements have the same number of electronic shells.
Who made and what is the plum pudding model.
JJ Thompson
When there is a ball with positive and negative charge spread out.
What is the nuclear model
It has a dense positive centre with negative charge randomly around it.
Period table: 1808 John Dalton
Ordered element through the atomic weight
