atoms and PT basics

							Q: What’s an atom?

The smallest piece of matter that still
 has all the properties and
 characteristics of that type of matter

EX. An atom of gold still has the same
 chemical and physical properties as a
 chunk of gold
Q: What’s an atom?

Brownian Motion

  Perpetual movement of particles (atoms
   jiggling/vibrating)

  Named after Robert Brown (Scottish botanist).
Q: What does an atom look like?

An atom is mostly empty space

Atoms have a small, dense nucleus at
 their center

   Atoms contain what we call subatomic
        particles (3 subatomic particles)
Q: What does an atom look like?
(3 subatomic particles)
Electron (symbol e-)
   Location- electron cloud (outside nucleus)

   Charge- negative (each electron has a -1
   charge)

   Relative mass- 1/1840
     1/1840 the size of the other particles = SMALL
   Q: What does an atom look like?
       (3 subatomic particles)
Proton (symbol p+)
   Location- nucleus

   Charge- positive (each proton has a +1
   charge)

   Relative mass- 1
   Q: What does an atom look like?
       (3 subatomic particles)
Nucleus (symbol n0)
   Location- nucleus

   Charge- neutral (each neutron has zero
   charge, not charged at all!)

   Relative mass- 1
 Draw a picture of an atom below. Label
each of the three subatomic particles, as
 well as the nucleus and electron cloud.
Q: What is the overall charge of the
nucleus in an atom? Why?
Nucleus is made of protons and neutrons
 (p+ and n0)

Since the only charged particles are
 protons and they have a positive charge,
 the overall charge is positive
Break Time

Structure of the Atom Worksheet
 (ChemQuest 8) with questions
   Use the diagrams and information on the
    front of the sheet to answer the questions
    on the back.
Q: What is the Periodic Table?

Where we can look to find elements
   Any element in the world is found here. If
   it’s not here, it’s not an element.

  For example:
     Hydrogen and oxygen are found on the PT (H
     and O), they are both elements.
     Water is made of these elements (H2O), but is
     not found on the PT. Water is a COMPOUND, not
     an element
Q: What is the Periodic Table?
The table is organized based on physical
 and chemical properties/characteristics
 of elements such as:
  What will happen when it is mixed with a certain
   chemical?
   How many of each subatomic particle are
   present?
  What state of matter is it at room temperature?
   What does it look like (shiny, dull, etc)?
  How big is an atom of that element?
Q: How do I read the periodic table?

First, you must realize that each box
 contains information about ONE
 ELEMENT
Q: How do I read the periodic table?

The smaller number in each box (usually
 at the top) is called the atomic number.
  Tells us how many p+ an atom of that element
   has
  Tells us how many e- an atom of that element
   has
    *** This is true ONLY if the atom has an overall
     NEUTRAL CHARGE
Atomic Number


             8      Atomic
                    Number

            O
           Oxygen
           15.999
Q: How do I read the periodic table?

The larger number (usually at the bottom)
 represents the atomic mass.
   Measured in amu (atomic mass units)
   Tells us the total number of p+ and n0 in an
   atom
   How can I use this to find JUST the number of
   n0?
     Atomic mass – Atomic number = # n0
     Atomic mass MUST be rounded to the nearest
     whole number
Atomic Mass


                8

               O
              Oxygen
                       Atomic
              15.999   Mass
                       (amu)
Q: How do I read the periodic table?

 Chemical Symbol
   Usually only one or two letters
   Some have three letters- these are manmade
   and will likely get renamed.
   First letter is always capital, second is always
   lowercase
   Some symbols are based on the Latin names
   for the element
     Ex. Aurum – gold – Au
          Ferrum – iron – Fe
  Chemical Symbol and Name


               8



Chemical
              O          Chemical
                         Symbol
             Oxygen
   Name
             15.999
Example: Find the element Bismuth
(Bi) on your PT.

    Atomic Number: 83
    Atomic Mass: 207 (approx)
    Symbol: Bi
    # p+ = 83
    # e- = 83
    # n0 = 124 (207 – 83)
Agenda Items

Atomic Math Challenge- due tomorrow