there are three states of matter: gas, solid and liquid all matter is made of atoms an element is...
DESCRIPTION
+ Nucleus Electrons Neutron (neutral) Protons AtomTRANSCRIPT
There are three states of matter: gas, solid and liquid
All matter is made of atoms
An element is made up of one type of atom
A molecule is a combination of two or more atoms. (They can be the same
element or different elements)
• All atoms have a central part called a nucleus
• The nucleus is made up of two structures, protons that have a positive charge and neutrons which have no charge
• Orbiting around the nucleus are structures called electrons. They carry a negative charge. They are the smallest of the three structures
• Most atoms have the same number of electrons and protons
+
Nucleus
ElectronsNeutron
(neutral)
Protons
Atom
Periodic Table
HeHelium
2
4.0
Symbol
Element Name
Atomic Number
Atomic Weight
Periodic Table The atomic number represents the number of electrons and protons
HeHelium
2
4.0
Symbol
Element Name
Atomic Number
Atomic Weight
The number of neutrons is
calculated by subtracting the Atomic number from the Atomic
Weight
4-2 = 2 neutrons in a Helium atom