1. Chapter 2
Matter & Change

2. Matter Anything that has mass & takes up space
All materials you hold or touch
Air you breathe

3. Mass = a measure of the amount of matter an object contains
Volume = measure of the space occupied by an object
Substance = type of matter with a fixed composition (can be an element or a compound)

4. Physical Properties
Quality or condition of a substance that can be observed or measured without changing the substances composition
color, shape, odor, texture, density

5. Intensive Properties
Physical properties depend upon the type of matter in a sample, not the amount, it helps you determine what a substance is
Melting point, Density, Viscosity, Color
Every sample of a given substance has the identical intensive properties because every sample has the same composition

6. Extensive Properties
Physical properties that depend upon the amount of matter in a sample on hand & do not help you determine what a substance is
Mass
Length
Volume

7. This blue crystal has a mass of 0.32g and a density of 3.20 g/cm3.
It is not malleable and has a volume of 0.1 cm3
Which properties listed are intensive?
3.2 g/cm3, not malleable, blue
Which properties listed are extensive?
0.32g, 0.1cm3

8. Physical Change
Properties of a material change; however, the composition of the material does not change
Occurs in a substances if there is a change in state but not change in the identity of the substance
Can be reversible - melting, boiling
Can be Irreversible - slicing, cutting

9. Chemical Properties of Matter
The way a substance reacts with another to form a new substance with different properties
Involve reactivity – ability of a substance to combine chemically with another substance
Chemical properties of compounds vary from the individual elements that they are made from

10. Chemical Changes changes in composition
atoms are changed or rearranged to form a new substance with new chemical properties and new physical properties
bumper with rust

11. Recognizing chemical change
When a chemical change occurs there are indicators that blatantly let you know. Some are listed below:
Change in color
Precipitate
Formation of gas
Change in Mp or Bp

12. States of Matter: Solid
Particles are in a fixed position – therefore, they have a rigid structure
Particles have almost no freedom to change position; they change position around a fixed point
Not easily compressed
Definite shape
Definite volume

13. States of Matter: Liquid
Particles are close together and move freely around each other
Indefinite shape but a definite volume
Liquids vary in viscosity (the resistance of a fluid to flow – thickness)
Not easily compressed
Fixed volume, no fixed shape. Liquids take the shape of their container as far as the fixed volume goes

14. States of Matter: Gas Indefinite shape, indefinite volume
Takes the same shape and volume as its container – spreads out to completely fill it
Particles expand to fill available space, move constantly and rarely stick together
Particles more very fast
Gas exerts pressure (force exerted per unit area of a surface) and will escape its container if possible – balloons, propane tanks, gas grills
Easily compressed

17. Mixture
a combination of two or more substances that are physically mixed but not chemically combined
Two or more substances in different proportions
Can be separated by physical methods

18. Homogeneous Mixture
contains two or more gases, liquids, or solids that are blended evenly throughout
Different parts of the mixture are not visible
Brass is a mixture of copper and zinc

19. Scuba Breathing Mixtures
Breathing mixtures for scuba are homogeneous mixtures. Some examples are
Nitrox (O2 and N2 gases)
Heliox (O2 and He gases)
Trimix (O2, He, and N2 gases)

20. Heterogeneous Mixture
a mixture in which different materials can be distinguished easily
The composition varies from one part of the mixture to another
Fruit salad, trail mix, granite

21. Heterogeneous HomogeneousP
Which is which?
Heterogeneous Homogeneous

22. Separating Mixtures
Filtration = separates a solid from the liquid in a heterogeneous mixture
Distillation = process used to separate dissolved solids from a liquid (boiling and then condensing)
Evaporation

23. Pure substances Type of matter with fixed or definite composition
Every sample has identical intensive properties because every sample has the same composition
Compounds
Elements

24. Elements composed of one type of atom
substance that cannot be broken down into simpler substances
Include
Copper, Cu
Lead, Pb
The element copper consists of only copper atoms

25. Compound
two or more elements that are chemically combined in a definite ratio such as
Hydrogen peroxide H2O2
Sodium chloride NaCl
Dihydrogen monoxide H2O
can be broken down into simpler substances

27. Law of Conservation of Mass
Mass can not be created or destroyed
Total mass of all matter stays the same as before the change – it changes from one form to another
From ice to liquid to gas, it will all have the same mass

28. Molecules
Molecule  smallest unit of a substance that exhibits all of the properties characteristic of that substance

29. Chemical Formula
Chemical shorthand that uses symbols and numbers indicating the elements in a compound and their ratios
C6H8N4O2  Theobromine (chocolate)
C6H12O6  Fructose (sugar)

30. Hydrogen combines with oxygen to produce water
Chemical Reaction
Hydrogen combines with oxygen to produce water
H2 + O2  H2O
Reactants  Products

31. The End