UNDERSTANDING MATTER AND CHEMICAL CHANGE The universe is made up of two things : matter and energy

MATTER Matter is made up of particles These particles are made up of elements (from the periodic table

ENERGY Energy is the different forces that make particles do something i.e. fusion (stars), electromagnetic fields, fission (atomic bombs), a push or pull

PARTICLE THEORY OF MATTER All matter is made up of very small particles

Each pure substance has its own kind of particle, different from the particles of other pure substances

Particles attract each other

There are spaces between particles

Particles are always moving.

As particles gain energy they move faster As particles gain energy they move faster. Particles at higher temperature move faster than particles at lower temperatures

3 STATES OF MATTER (ON EARTH) Solid Liquid Gas

HEY! WHAT ABOUT PLASMA???? Only in stars (like our sun) or in a laboratory

WHAT IS MATTER?

How do you classify matter?

MATTER Pure substances Mixtures

Which is the pure substance? Which is the mixture?

Why does a chemist care?

MATTER Pure substances Mixtures

Pure substances Compounds Elements

COMPOUNDS NaCl H2O (chemical formulas)

Elements (on the periodic table)

HOW CAN WE TELL THE DIFFERENCE BETWEEN ELEMENTS AND COMPOUNDS?

Compounds can be broken down into simpler units by heat and/or electricity. NaCl Na Cl

ELEMENTS CANNOT BE BROKEN DOWN CHEMICALLY INTO SIMPLER UNITS BY HEAT OR ELECTRICITY

LEARNING CHECK: ELEMENT OR COMPOUND? H2O C6H12O6 (glucose – sugar made in photosynthesis Zn Fe

MATTER Pure substances Compounds Elements Mixtures

Same properties throughout SOLUTIONS Mixtures Homogeneous mixtures Heterogeneous mixtures Same properties throughout SOLUTIONS Different properties in small samples SALSA, MILK

LEARNING CHECK: HOMOGENEOUS OR HETEROGENEOUS MIXTURE coke milk bowl of cereal koolaid gatorade salad dressing your junk drawer sand at the beach a bucket of sea water salt water you make by dissolving salt in warm water

A good way to tell the difference between a homogeneous and a heterogeneous liquid: If you shine a flashlight through a homogeneous mixture the light will go through and the liquid seems clear (even if colored). If you shine a flashlight through a heterogeneous liquid like milk – the light is dispersed by the particles so the liquid is murky.

LEARNING CHECK: COLLOID? SOLUTION?

Heterogeneous mixtures Ordinary mechanical mixtures Big particles stay mixed (granite, salsa, choc chip cookie) Suspensions Large particles in liquid that settle (flour, charcoal) Colloids fine particles in a substance (gels, clouds) Emulsions Liquid in liquid (milk, mayo, salad dressings)

HETEROGENEOUS MIXTURES MATTER PURE SUBSTANCES ELEMENTS COMPOUNDS MIXTURES HETEROGENEOUS MIXTURES HOMOGENEOUS MIXTURES