Mind Map Gallery Atom Element Compound
An element is a substance that is made entirely of one type of atom. For example, the element sodium is made up of only sodium atoms.Edited at 2020-10-08 06:22:48
What is Matter?
Matter can change between the 3 states: solidto liquid (melting), liquid to gas (evaporation),gas to liquid (condensation), liquid to sold(freezing), solid to gas (sublimation), and gas tosolid (deposition)
Particle theory of matter: matter is composedof tiny objects called particles, particles havespace between them, particles are always inmotion, and particles in a substance attracteach other.
Classifies as a pure substance or a mixture
Pure substances are either elements orcompounds.
Mixtures can be heterogenous or homogenous.
Can be easily reversed
Colour and lustre
Results in the formation of a new substace
cannot be reversed easily
formed when nonmetals combine
can be any of the 3 states at room temperature
good insulators, poor conductors
Low boiling points
Naming molecular compounds
First element always stays the same
second element changes to end in "ide"
Identify symbol of first element
Identify symbol of second element
Add subscripts to indicate the amount
Important Discoveries that Shaped AtomicTheory
Matter is made of small invisible atoms
Atoms of an element are identical in properties
Atoms of different elements have differentproperties
Atoms of different elements can combine toform new substances
Used a cathode ray
Argued that all elements contain electrons
Atoms were composed of smaller particles
Created Thomson's model
Shot positive charged particles at pure gold
Discovered the nucleus
Revised Thomson's model
Each neutron carries about the same mass aseach proton.
Created Bohr diagrams
Shows that electrons reside in shells and jumpbetween each shell by gaining or losingelectrons
First shell has a maximum of two electrons
Every other shell has a maximum of eightelectrons
Quantum Mechanical Model: electrons exist inspecific energy levels as a cloud
Alloys are a mixture of two or more metals
Metals: shiny, silver or grey in colour, greatconductors, and malleable.
Nonmetals: there are only 17 elements
Metalloids have metallic and nonmetallicproperties and are semiconductors.
A Summary of the Atom
Resides in the nucleus
Has an electric charge of 1+
Has a relative mass of 1836
Resides in the nucleus
Has an electric charge of 0
Has a relative mass of 1837
Resides in energy levels surrounding thenucleus.
Has an electric charge of 1
Has a relative mass of 1
The Element Symbols
Each element has its own symbol
First letter is capital and the second islowercase.
The Periodic Table
Atomic theory supports the periodic table
Group 1 elements lose 1 electron (1+ charge)
Group 2 elements lose 2 electrons (2+ charge)
Group 312 elements lose different numbers ofelectrons
Group 13 elements lose 3 electrons (3+ charge)
Group 14 elements can lose or gain 4 electrons(4+ 4 charge)
Group 15 elements gain 3 electrons (3 charge)
Group 16 elements gain 2 electrons (2 charge)
Group 17 elements gain 1 electron (1 charge)
Group 18 elements gain no electrons (0)
Lewis structures show the valence electrons ofan atom.
High melting points
dissolves in water
becomes said at room temperature
Naming Ionic Compounds
First element stays the same
Second element ends in &quot;ide&quot;