PERIODIC TABLE
HISTORY
• Developed by Dmitri Mendeleev, Russian Scientist in 1869
• 63 elements
• Arranged by increasing atomic weight an...
GROUPS – VERTICAL COLUMNS
• 1 – alkali metals
• 2 - alkaline earth metals
• 7 - halogens
• 0 – inert gases or noble gases
...
PERIODS – HORIZONTAL ROWS
• Numbered 1-7
• Transition metals are between groups 2 and 3
• Metals (<3/4) and nonmetals (<1/...
GROUP 1 – ALKALI METALS
• Lithium, sodium, potassium, rubidium, caesium and radioactive francium.
• Very reactive metals –...
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Periodic table

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Periodic table

  1. 1. PERIODIC TABLE
  2. 2. HISTORY • Developed by Dmitri Mendeleev, Russian Scientist in 1869 • 63 elements • Arranged by increasing atomic weight and properties. • Today’s table has been modified based on the work of Rutherford and Moseley. • Arranged by atomic #, 115 elements
  3. 3. GROUPS – VERTICAL COLUMNS • 1 – alkali metals • 2 - alkaline earth metals • 7 - halogens • 0 – inert gases or noble gases • Trends • All elements in a group have the same number of valence electrons • (exception noble gases have either 2 or 8) • Valence electrons are mostly responsible for chemical properties of an element.
  4. 4. PERIODS – HORIZONTAL ROWS • Numbered 1-7 • Transition metals are between groups 2 and 3 • Metals (<3/4) and nonmetals (<1/4) • Metalloids – act like both metals and nonmetals • Trends across a period • From metal to nonmetal • Increase in number of electrons in the outer energy shell • Giant metallic through giant covalent to simple molecular
  5. 5. GROUP 1 – ALKALI METALS • Lithium, sodium, potassium, rubidium, caesium and radioactive francium. • Very reactive metals – stored in oil to prevent contact with air or water. • Good conductors of electricity and heat • Soft metals (lithium is hardest, potassium is softest) • Low densities • Shiny surfaces when freshly cut with knife • Low m.p. • Tend to lose one electron to form a stable outer energy level and a +1 charge • More reactive as you go down the group because it takes more energy to remove an electron closer to the nucleus. • Burn in oxygen to form solid oxides • Dissolve in water to form alkaline (basic) solutions of metal hydroxide. • React vigorously with water to for alkaline solution and hydrogen gas. • React vigorously with halogens to form metal halides.

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