Thirsty for Chemistry?

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Thirsty for Chemistry?

• Ive gotta ask..
• Are You

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Color Change Demonstration
Get a beaker
No, not that Beaker.
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Color Change Demonstration
Water Water Baking Soda
Fruit Punch Phenolphthalein (Think CSI)
Milk Barium Chloride
Dichromate Hydrochloric acid
These are toxic, you cannot drink them!!
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Its All in the Atom

• An Intro to Elements and the Periodic Table

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Elements

• Robert Boyle (1627-1691) gave the basis for
  modern definition of an element
• An element is a pure substance that cannot be
  chemically broken down into a simpler substance.
• Every element has its own atomic structure,
  which we call an atom

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Parts of an Atom

• An atom is made up of 3 types of particles.
• 1) The electron (e-)
• Has a charge of -1
• Has relatively no mass
• Is found in an orbital/shell, around the nucleus
  of an atom

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Parts of an Atom

• 2) The proton (p)
• Has a charge of 1
• Has a mass of 1 amu
• Amu Atomic Mass Unit
• Is found in the nucleus of the atom

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Parts of an Atom

• 3) the neutron (n)
• Has NO charge
• Has a mass of 1 amu
• Is found in the nucleus of the atom

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Bohr Diagram of the Atom

• Niels Bohr was a Danish physicist.
• He proposed a model of an atom where
• protons and neutrons are located in the centre
  of the atom (nucleus)
• and the electrons move around the nucleus in
  orbits called shells

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Bohr Diagrams

• Each shell can hold a specific number of
  electrons.
• K-shell is the first shell and can hold 2
  electrons
• L-shell is the second shell and can hold 8
  electrons
• M-shell is the third shell and can hold 8
  electrons
• Remember Neutral atoms always have the same
  number of electrons as protons (charges cancel)

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Bohr Diagrams

• E.g-a boron atom has 5 p, 5 e-, and 6 n. Draw
  the Bohr diagram

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Bohr Diagrams

• A beryillium atom has 4 p, 4 e-, and 5n. Draw
  it

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Bohr Diagram

• A phosphorus atom has 15 p, 15 e-, and 16 n.
  Draw it

15 p 16 n
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Reading from the Periodic Table

• Each element in the periodic table is represented
  by a symbol.
• Every symbol has an upper case letter.
• Some symbols have two letters.
• The first is upper case
• The second is lower case (e.g. Ca is calcium)

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• E.g.
• C is the symbol for carbon
• Cl is the symbol for chlorine
• Cu is the symbol for copper

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Atomic Number

• Is the number of protons that an atom has.
• Each element has a unique atomic number.
• Every element is arranged according to atomic
  number on the periodic table.
• Atomic number of p

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Atomic Number
Is found in the top left-hand corner
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Atomic Mass

• Is the mass of the atom in amu.
• Since each proton has a mass of 1 amu, and each
  neutron has a mass of 1 amu, then the atomic mass
  is equal to the number of protons and neutrons.
• Atomic mass
• protons neutrons

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Atomic Mass

• E.g. Nitrogen has 7 p and 7 n.
• So, atomic mass 7 7 14 amu

Is found under the symbol.
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On Your Periodic Table
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Assignment

• Use your periodic table to fill in the table on
  page 4. Well do a few together.

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Symbol Name Atomic Atomic mass P e- n
Li Lithium 3 7 3 3 4
O Oxygen 8 16 8 8 8
P Phosphorus 15 31 15 15 16
F Flourine 9 19 9 9 10
Br bromine 35 80 35 35 45
Fe iron 26 56 26 26 30
K potassium 19 39 19 19 20
Bi bismuth 83 210 83 83 127
Pb lead 82 207 82 82 125