Chemistry 2 Flashcards
(35 cards)
What are all substances made of?
Atoms
Atom
The smallest unit of matter that can exist in its own
Where are the types of atom listed?
The periodic table of the elements
How many naturally occurring elements are there?
92
What do we call the Vertical columns on the periodic table?
Groups
What do we call the Horizontal rows on the periodic table?
Periods
Element
A substance made up of only one type of atom
Subatomic particles
The particles that make up atoms
Which three subatomic particles are atoms made of?
Protons, neutrons, electrons
What is found in the centre of an atom?
Nucleus
Which subatomic particles are found in the nucleus?
Protons and neutrons
Where are the electrons found?
In shells around the nucleus
Atomic Number
Number of protons
Atomic mass
Number of protons and neutrons
How many electrons do atoms have?
The same as the number of protons
What is the maximum number of electrons that can be held in each shell?
First shell - 2
Second shell - 8
Third shell - 8
What does the group number tell you about the electrons?
The number of electrons in the outer shell
What does the period number tell us about the electrons?
The amount of shells
How many elements are there in total?
118 elements
What are the letters called that represent an atom?
Chemical symbol
Molecule
A small number of atoms joined together
Chemical formulae
The chemical symbol and the number of each atom
Oxygen
O₂
Water
H₂O
