Download Sci 9 Unit 2 Topic 1

Science 9
Unit 2- Matter and Chemical Change
Topic 1- Exploring Matter
Chemistry
• The study of the properties of matter and the
changes matter undergoes
• Much of what we know today was not discovered in
fancy labs using expensive equipment
• Many scientists were very poor and dedicated their
lives to research without pay
Safety in the Lab
• Some scientists in the past routinely tasted and
smelled chemicals which is extremely dangerous
• some chemicals are caustic and can burn, corrode, or
destroy organic tissues
• The chemicals, equipment,
and procedures used in the lab
must always meet safety
guidelines such as wearing
the appropriate equipment
Classifying Matter
• The Particle Model of Matter:
1) All matter is made up of tiny particles
2) Each pure substance is its own particle, different from
other particles of other substances
3) Particles attract each other
4) Particles are always moving
5) Particles at higher
temperatures move faster
than particles at low temperatures
The Particle Model
• Scientific models help us to visualize the processes
that cannot be seen directly
• Matter can be classified according to its state as a
solid, liquid, or a gas
Chemical Composition
• Matter can be further classified according to its
composition as a mixture or a pure substance.
Mixtures contain at least 2 substances and a pure
substance is its own kind of particle
• Mixtures can be classified as homogenous (particles
uniformly scattered) and heterogeneous (not
uniformly scattered)
Mixtures of Matter
• Solutions are homogenous mixtures that are usually clear
and can not be separated
• Mechanical mixtures are heterogeneous mixtures where
the parts are large enough to see
• Suspension is a heterogeneous mixture made of large
particles that are uniformly mixed but will settle if left
undisturbed-ex. Flour in water
• Colloids are composed of fine particles evenly distributed
throughout a second substance- ex. Hair gel and clouds
• Emulsions are colloids where liquid is mixed in liquid ex.
Mixed up oil and vinegar salad dressing
Spot the Mixture??