The Nature of Matter

1
The Nature of Matter

• Physical Sciences

2
Benchmarks

• A. Describe that matter is made of minute
  particles called atoms and that atoms are
  comprised of even smaller components. Explain
  the structure and properties of atoms.
• B. Explain how atoms react with each other to
  form substances and how molecules react with each
  other or other atoms to form even different
  substance.
• C. Describe the identifiable physical properties
  of substances (e.g., color, hardness,
  conductivity, density, concentration, pH, and
  ductility). Explain how changes in these
  properties can occur without changing the
  chemical nature of the substance.
• H. Trace the historical development of
  scientific theories and ideas, and describe
  emerging issues in the study of physical sciences.

3
Defining Matter
Matter - anything that has mass and takes up
space. Mass - the total amount of material in an
object. Tool to measure - triple beam
balance Units - mg, g, kg, etc.
4
Defining Matter

• Volume - the amount of space an object occupies.
• The volume of liquids can be measured using a
• graduated cylinder or beaker.
• Units are liters (L) or milliliter (mL).
• The volume of irregular shaped objects are
  measured using water displacement with a
  graduated cylinder or beaker.
• Units are liters (L) or milliliter (mL).

5
Defining Matter

• The volume of a cube can be calculated by
  measuring the length of one side using a
  meterstick or ruler.
• V length X height X width
• Ex. If the length of one side of a cube is 2
  cm, what is the volume?
• V 2 cm X 2 cm X 2 cm
• V 8 cm3

6
Defining Matter

• Density - the amount of matter in a given space.
• D mass / volume
• Mass and volume both need to measured separately!
  The calculation (ratio) of the two measurements
  equals the density.
• Ex. If the mass of a cube is 54 grams and the
  length of a side is 3 cm., what is the density of
  the cube?
• First solve for volume V L X h X w
• V 3cm X 3cm X 3cm
• V 27 cm3
• Density mass 54 g 2
  g/cm3
• volume 27 cm3

7
CHEMISTRY

• Chemistry is the science that investigates and
  explains the structure and properties of matter.
• Composition - what matter is made of and how it
  is organized
• Elements- cannot be broken down into simpler
  substances.
• Compounds- a combination of two or more elements.

8
Chemistry

• Properties - describes the characteristics,
  composition and behavior of matter, including the
  changes that matter undergoes.
• 1. Physical - characteristics that a sample of
  matter exhibits without any change in its
  identity. Solubility, melting point, boiling
  point, color, density, electrical conductivity,
  physical state.
• 2. Chemical - can be observed when there is a
  change in the composition of the substance. Iron
  at room temp with air iron oxide (rust).

9
Chemistry

• Elements - the building blocks of matter, a pure
  substance, made up of one type of atom.
• Atom - the smallest particle of an element that
  has the properties of that element.
• Substance - made up of one or more elements.
• Compound - a combination of two or more atoms
  that maintains its own properties.
• Molecule- smallest particle of a substance that
  retains all the properties of the substance and
  is composed of one or more atoms.

10
History

• Greek philosophers (Democritus) created theories
  about indivisible matter Atomos - meaning
  that which cannot be cut or divided.
  
• Aristotle theorizes that everything is composed
  of Earth, Water, Air, and Fire.

11
History

• Early 1800s, John Dalton created the atomic
  theory (4 parts)
• 1. All elements are made up of atoms. Atoms
  cannot be created, divided,or destroyed.
• 2. All atoms of the same element have the same
  size and mass.
• 3. Atoms of different elements have different
  sizes and masses.
  
• 4. During a chemical reaction, atoms are not
  destroyed, just rearranged.
• Nuclear power disproves theorem number one.
  (Fission and Fusion)

12
Periodic Table
13
The Periodic Table

• 1869 Periodic table began to be organized by
• Dmitri Mendeleev.
• He organized elements due to physical and
• chemical characteristics.
• 1. This was later called atomic number
• a. number of protons
• b. number of protons determines
  of
• electrons
• 2. Periodic repetition of properties
• www.chemicalelements.com/

14
The Periodic Table

• 3. Elements in columns are called groups or
  families
• a. Total of 18 groups
• b. Groups have similar characteristics
  and same of valence
• electrons
• 1. Ve- electrons in outer shell
• c. as elements descend atoms grow larger
• 4. Elements in rows are called series or periods
• a. elements are arranged by inc. of
  protons (atomic )
• b. Total of 7 periods
• c. Descending periods increase electrons
  in shells. This is due to increasing mass.
• d. As one goes across period atoms grow
  smaller.This is due to
• force of charge pulling in electrons.

15
Element Sizes
16
Atomic Mass and Numbers
Atomic Number number of protons Number
of protons determines the number of electrons
in a neutral atom.

• Atomic Mass - Average mass of all of the
  isotopes.
• Atomic Mass Number number of protons and
  neutrons
• Atomic mass minus atomic number
• equals the number of Neutrons.

17
The Periodic Table
Atomic Number

• 3
• Li
• Lithium
• 6.941

Lithium Protons3 Electrons3 Atomic
Mass6.941 Mass Number7 Neutrons4
Symbol
Name
Atomic mass
18
Atomic Structure

• Subatomic Particles the particles below the
  surface of an atom. This includes protons,
  neutrons and electrons. An electrical force
  between nucleus and electrons holds the atom
  together.
• atom smallest particle of an element that has
  the chemical properties of that element.
• 1. a billion atoms laid end to end would
  make a line only 10cm long
• 2. atoms make up cells

19
Atomic Structure

• A. electron negatively charged particle orbits
  the nucleus
• 1. electron is first to be discovered - 1891
• 2. lightest subatomic particle
• B. proton positively charged particle
• 1. located in nucleus of atom - 1896
• 2. second lightest subatomic particle
• C. neutron neutrally charged particle
• 1. located with proton in nucleus - 1932
• D. nucleus holds protons and neutrons of atom
• 1. discovered in 1910
• 2. atoms are mostly empty space,distance
  between nucleus and electron is like a marble on
  the pitchers mound of a baseball field and the
  furthest seat in the stadium would be the
  electron.

20
Atomic Models

• Electron Cloud Bohrs
  Model

21
Particle Behavior

• Hunds Rule electrons are negative, they have
  same charge and repel from each other, as far
  apart as possible.
• Heisenberg Uncertainty Principle 1920,
  impossible to measure accurately both
• the position and energy of an electron at
• the same time.

22
Electron Configurations

• These are the most stable arrangement of
  electrons
• There are 4 regions s,p,d,f
• s holds total of 2 electrons ___
• p holds total of 6 electrons ___
  ___ ___
• d holds 10 electrons ___ ___ ___
  ___ ___
• f holds total of 14 electrons ___
  ___ ___ ___ ___ ___ ___
• Shells will fill up one at a time (like seats on
  a bus)