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Properties of Matter
Properties of Matter
• Characteristics of a substance
Physical Properties• characteristics that can be observed without
changing the chemical identity of the substance– Not dependent on amount of sample
AppearanceOdorMelting PointBoiling PointDensity
HardnessTextureDuctility/MalleabilitySolubilityElectrical/Thermal
ConductivityMagnetism
Chemical Properties• Characteristics that describe the ways a substance can
react to form new materials– Cannot be observed without changing the chemical
composition of the substance
• Examples
FlammabilityReaction with OxygenReaction with Water
Decomposition by lightDecomposition by heatTendency to Corrode
Physical Changes• Changes that do not result in the formation of
a new substance– Chemical bonds have not been broken or formed;
the molecules are still connected in the same way• Change of state• Change in appearance
Chemical Changes• Changes in the chemical bonds of a substance
– Always produce a new substance– Chemical bonds are broken and/or formed
– Signs:• Visible flame• Color change • Bubbling/Fizzing• Smoke• Heat/Light given off• Formation of a substance in a different state
Kinds of Matter• Elements
– cannot be broken down into any other substance– All matter is composed of elements.– Each element is made of a specific type of ATOM
• Ex: Oxygen
• Ex: Hydrogen
Kinds of Matter
• Compounds– two or more elements chemically combined in a
specific ratio
Kinds of Matter
• Mixtures– two substances that are together in the same
place but are NOT chemically combined
States of Matter• Matter is made of tiny particles that are in
constant, random motion– can be classified as a solid, liquid, gas, or plasma
depending on the motion and arrangement of the particles
Solid• Particles do not move freely, but vibrate in
place– Packed tightly together, usually arranged in a
specific & fixed pattern• Definite volume• Definite shape
Liquid• Particles move freely
– Fairly close together, but not in a fixed pattern• Definite volume• Indefinite shape (take shape of container)
– Viscosity: resistance to flow• High viscosity – slow flow (honey)• Low viscosity – easy flow (water)
Gas• Particles move very energetically in all
directions– Very fast and far apart
• Indefinite volume (take up all available space)• Indefinite shape (take shape of container)
Plasma• Particles have extremely high energy
– Highly energetic charged particles that move independently
– Extremely fast and far apart• Most of the matter in the universe!
Particle Motion• Solids – particles tend to move slowly (vibrate) and keep
their shape• Liquids – particles move freely and take the shape of
their container• Gasses – particles move excitedly and fill all available
space• Plasmas – charged particles move extremely excitedly
and fill all available spaceWhat misconceptions could be created by the model shown here of particles in a solid, liquid, gas, and plasma?
Phase Changes• Transfer of heat energy is
required to change the state (or phase) of a substance– Freezing/Melting Point– Boiling/Condensation Point
Argon Ice melting and sublimating at the same moment
Phase Graphs
Draw your own Phase Graph
Density• Density is a measure of how closely packed
the atoms are in a substance• Density will change as temperature changes
– As a substance is heated, particles tend to spread, making it less dense (ice is an exception)
– Solids tend to be more dense than liquids; liquids tend to be more dense than gasses.
Calculating Density• Density equals mass divided by volume• d = m/v
– Mass usually measured in grams (g)– Volume either found by displacement or calculated
using a formula (mL, cm3, or cc)• Units: g/mL or g/cm3 or g/cc
Sinking and Floating• Density determines whether an object will sink
or float.• Substances/Objects that are
more dense will sink in substances that are less dense.
• Substances/Objects that are less dense will float in substances that are more dense.– The diet coke is less dense than
water. The regular coke is more dense than water. • Coke = 1.042 g/mL Diet Coke = 0.997g/mL• Water = 1.000 g/mL
Conductivity• Electrical Conductivity – the ability of a substance to
allow electrical energy to flow through it• Thermal Conductivity – the ability of a substance to allow
thermal energy to flow through it– Both are related to density
• CONDUCTORS: more dense materials tend to be better conductors (allow energy to flow through them easily)
• INSULATORS: less dense materials tend to be poor conductors (resist the flow of energy through them)
Special Properties of Water• Unlike most substances, the freezing point and
boiling point of water allow it to exist as a solid, liquid, and gas at natural Earth temperatures
Special Properties of Water• Water heats up & cools down very slowly
compared to other substances– Due to a property called “specific heat”– This maintains a moderate environment on Earth that
is suitable for life
Special Properties of Water• Water forms “polar molecules”, creating “hydrogen
bonds” between molecules. This results in…– Cohesion – water molecules attracted to each other
– Adhesion – water molecules attracted to other substances
Special Properties of Water• Water is called the “universal solvent”
– Many other substances dissolve in water• The water we encounter is rarely pure because so many
minerals can easily dissolve in it.