Matter

1
Matter

• All matter has Mass and Volume.
• Every sample of matter is either an element, a
  compound, or a mixture.

2
Element

• A substance that cannot be broken down
• into simpler substances by
• chemical means.

3
Atoms

• Each element is made of one kind of atom.
• Atoms are the smallest unit of an element
• that maintains the chemical properties of
• that element.

4
Symbols

• Short hand way of writing element names.
• First letter capital. All others are lower case.
• One, two or three letters.
• Print like in kindergarten.

5
Elements of the Human BodyIn order of amounts

• Oxygen about 66 of body.
• Carbon about 18.
• Hydrogen about 10.
• Potassium, calcium, sulfur,nitrogen, phosphorus,
  sodium 2 or less.

6
Molecule

• Smallest unit of substance that behaves like the
  substance.
• Examples H2O, O2

7
Compounds

• Substance made up of atoms of different elements.
• Each molecule of a compound contains 2 or more
  elements that are chemically combined.
• They combine in the same proportions.
• Example- NaCl, KOH

8
Compounds

• Have unique properties
• Have properties unlike elements that combine to
  make the compound.

9
Chemical Formula

• Shows how many atoms of each element make up the
  compound
• The number of atoms is written as a subscript
  after the elements symbol.
• If only one atom, then no subscript.
• NO, NO ones.
• Numbers in front of compound show molecules.
• Example 3H2O

10
Pure Substances

• Pure substance- matter that has a fixed
  composition.
• Elements and compounds are pure substances.
• Pure substances can not be separated into parts.
• They are chemically combined and can not be
  physically separated.

11
Mixtures

• Combination of substances that are not chemically
  combined
• Can be separated into their parts
• Classified by how well they mix

12
Types of Mixtures

• Homogeneous Mixture
• Heterogeneous Mixture

13
Homogeneous Mixture

• Components are evenly distributed
• Mixture is the same throughout
• Can also be called a solution.
• Example- gasoline-100 liquids
• Gasoline is misicible.
• Miscible- able to be mixed.
• Immiscible-will not mix
• Example- oil and water

14
Heterogeneous Mixture

• Substances not evenly distributed
• Some are hard to recognize.
• Ex. Shirt- cotton and polyester
• salad

15
Miscible and Immiscible

• Gasoline is miscible.
• Miscible- able to be mixed.
• Immiscible-will not mix
• Example- oil and water
• Gases can mix with liquids.
• Gas-liquid mixture-
• carbonated drinks
• gas in drink and air bubbles
• foam
• egg whites

16
Properties of Matter

• Physical properties
• Chemical properties

17
Physical Properties

• Characterists that can be observed without
  changing the identity of the substance
• Can help identify substances
• state, color
• Can be observed and measured
• boiling point- the temp at which a liquid
  changes
• to a gas
• melting point-the temp at which a solid
  changes
• to a liquid
• Help determine uses-antifreeze, aluminum foil
• Example-strength, hardness, magnetism, ability to
  
• conduct heat or electricity, density

18
Density

• Dm/v
• Measure of how much matter is contained in a
  certain volume of a substance
• Units- example- g/cm3, g/ml, cg/ml
• Water has a density of 1g/cm3
• A cubic centimeter has the same volume as a
  milliliter.

19
Density, Mass, Weight

• Density is different from Mass.
• Mass and weight are different.
• D mass/volume
• Mass- amount of substance
• Weight- pull of gravity on a substance.

20
Chemical Properties

• Describes how a substance changes into a new
  substance, by
• 1. combining with other elements
• 2. breaking apart into new substances
• Example- 1. Flammability ability to burn
• 2. Nonflammability-does not burn
• 3. Reactivity- capacity of a
• substance to combine
  with
• another substance( iron
  O rust)

21
Chemical and Physical Properties

• Are not alike
• Can observe physical properties without changing
  the identity of the substance
• Can observe chemical properties only in
  situations in which the identity of the substance
  changes

22
Changes in Matter

• Physical Change-affects 1 or more physical
  properties of a substance without changing the
  identity of the substance
• Example- cutting hair, melting popsicle,
  crushing a can, sugar dissolving
• Do not change identity of substance
• During physical change-energy is absorbed or
  released, arrangement of atoms is the same even
  if looks different

23
Chemical Changes

• Chemical change- happens when one or more
  substances are changed into entirely new
  substances that have different properties.
• Examples- food digested, battery dies, oxygen
  breathed, fruit ripening

24
Chemical Changes

• Form new substances
• Interaction the action or influence between
  things
• Can be detected-
• change in color, odor, fizzing, foaming,
• sound, heat, light
• Chemical changes can not be reversed by
• physical changes.
• (bread baking, rust, milk turning sour)

25
Breaking Down Mixtures

• Mixtures can be separated by physical changes.
• Mixtures are not chemically combined.
• Breakdown by removing pieces, heat, distillation,
  centrifuge, evaporation

26
Breaking Down Compounds

• Breakdown through chemical changes
• heat, electric current, chemical changes