People

• Newlands

the first to arrange the elements into a periodic table with increasing order of atomic masses.

figured out that every eight elements had similar properties and called this the law of “octaves”.

• Mendeleev (1860’s)

created element cards

sorted elements by how they reacted and then sorted them from lightest to heaviest

created a basic periodic table that left gaps for undiscovered elements

• Ramsey (1894’s)

did not know there were shells because electrons had not yet been discovered

discovered Noble Gases

• Moseley

discovered atomic numbers (from 20+ they were not accurate)

Silicon, Germanium, and Arsenic are the main metalloids

Element Types

• Metals

  • Location

    • Everything on the left side of the table (except hydrogen)

  • Properties

    • Luster - Can be polished to make shine

    • Malleable - Can be shaped

    • Ductile - Can be stretched (into a wire)

    • Conductor - Electricity and heat can pass through it (conducts it)

    • Corrode - Reacts with elements in the atmosphere

• Non-Metals

  • Location

    • Everything on right side of table is a non-metal

  • Properties

    • Dull - Not shiny

    • Brittle - Breaks easily

    • Poor Conductor - Electricity and heat cannot pass through it

• Metalloids (Semi-Conductors)

  • Location

    • On the line (B, Si, Ge, As, Sb, Te, and At)

  • Properties

    • Has properties of metals and non-metals

  • Fact

    • Used in electronics

• Periodic Table of Elements

  

Elements

• Alkali Metals

  • Location

    • First row down - top is Hydrogen (H)

  • Properties

    • 1 Electron in Outer Shell

    • Most reactive metals

    • Make a base in water

• Alkaline Earth Metals

  • Location

    • Second row down - top is Beryllium (Be)

  • Properties

    • 2 Electrons in Outer Shell

    • 2nd most reactive metals

    • form an alkaline (base) solution when added to water

• Transition Metals

  • Location

    • Big gap in middle of Alkaline Earth Metals and Boron family

  • Properties

    • 1 or 2 Electrons in Outer Shell

    • Some are reactive (ex. iron and copper)

    • Some are not very reactive (ex. gold and platinum)

• Rare Earth Metals

  • Location

    • Bottom part of periodic table

• Halogens

  • Location

    • 7 Electrons in the Outer Shell

  • Properties

    • Most reactive non-metals

• Noble Gases

  • Location

    • Last row down - top is Helium (He)

  • Properties

    • Full outer shell

    • Most have 8 valence electrons (unsure ask)

    • Non-reacting under normal conditions similiar to old-time nobility and not being with the commoners

General

Coloumb’s Law

• Describes forces between charges

• If distance goes up force goes down

• Atoms get bigger going across in a row because of Coloumbe’s attraction

Atomic Size

• Row from top = shells

• row from side = valence electrons

• small elements on top

• large elements on bottom

• down = more valence electrons

• up = less valence electrons

Ionization Energy

• Lose electrons

• + Charge Ions

• Low for metal; high non-metals

Electron Affinity

• Gain electrons

• - Charge Ions

• High for metals; low non-metals

Atomic Properties

• Metals are generally more reactive at the bottom of the table than the top (rows 1,2,3)

• Non-Metals tend to be more reactive at the top of the table rather than the bottom (rows 4-8)

Period

• Across a period from left to right, the elements become less metallic and more non-metallic in their properties and smaller to larger