Elements and Their Properties

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Chapter 19

• Elements and Their Properties

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Metals

• Properties of Metals
• Conduct heat and electricity.
• Luster- reflect light well.
• Malleable- can be hammered or rolled into sheets.
• Ductile- can be drawn into wires.

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Metals- Cont.

• Ionic Bonds- combine with nonmetals by losing
  electrons.

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Metals- Cont.

• Metallic Bonds- positively charged metallic ions
  are surrounded by a cloud of electrons ions are
  in sliding layers and electrons are weakly held
  readily form ionic bonds with nonmetals.

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Alkali Metals

• The Alkali Metals- softer and more reactive than
  other metals.
• Highly reactive with oxygen and water dont
  occur naturally in elemental forms.
• Combine readily with other elements due to single
  electrons in the outer energy level.

Alkali Metals are found in Group 1 of the
Periodic Table.
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Alkali Metals- Cont.

• - Multiple uses
• Human Health- Na, K, Li
• Photocells- some depend on Ru or Cs
• Francium- a radioactive element which breaks down
  giving off particles and energy

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Alkaline Earth Metals

• Alkaline Earth Metals- not found naturally in
  elemental form two electrons in outer energy
  level.

Alkaline Earth Metals are found in Group 2 of the
Periodic Table.
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Alkaline Earth Metals

• Applications- Strontium and Magnesium found in
  fireworks Magnesium in vehicles, ladders, and
  bats Calcium in statues and countertops
• Human body- Calcium in
• bones Barium in disease
• diagnoses Radium
• formerly used in cancer
• treatment

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Transition Metals

• Transition Metals- they often occur in nature as
  uncombined elements

Transition Metals are found in Groups 3-12 of the
Periodic Table.
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Transition Metals- Cont.

• Typically form colored compounds- Chromium found
  in rubies and emeralds

Chromium in its raw form.
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Transition Metals- Cont.

• Iron Triad- Iron, Cobalt, and Nickel
• Iron- Most widely used of all metals and main
  ingredient in steel abundant in Earths crust
• Cobalt Nickel- used in some steels
• Nickel used to coat other metals

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Transition Metals- Cont.

• Copper, silver, gold- Coinage metals since once
  were commonly used in coins
• Copper- used in electric wiring because it is a
  superior electricity conductor.
• Silver- used in photographic film and paper,
  jewelry
• Gold- used in jewelry and fillings

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Transition Metals- Cont.

• Zinc, Cadmium, Mercury- Group 12 on the periodic
  table
• Zinc Cadmium- often used to coat or plate other
  metals
• Mercury- only room temperature liquid metal used
  in thermometers and batteries

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Transition Metals- Cont.

• Inner transition- seem disconnected from the rest
  of the periodic table
• Lanthanides- include La, Cr, Pr, Sm, Eu, Gd, Tb
• Actinides- all are radioactive and unstable
  Uranium is the best known

Uranium in raw form.
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Nonmetals

• Properties of Nonmetals
• Usually gases or brittle solids at room
  temperature
• Are not malleable or ductile
• Usually poor conductors of heat and electricity
• Usually not lustrous

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Non Metals- Cont.

• Ionic compounds form when nonmetals gain
  electrons from metals and become negative ions.
• Covalent compounds form when nonmetals share
  electrons with other nonmetals.

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Nonmetals- Cont.

• Hydrogen- most common element in universe
• Diatomic molecule- two atoms of the same element
  in a covalent compound
• Highly reactive element found mostly on Earth as
  part of a water compound

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Nonmetals- Cont.

• Halogens- include Bromine, Iodine, Fluorine,
  Chlorine, and Astatine

Halogens are found in group 17 of the periodic
table.
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Nonmetals- Cont.

• A salt forms when a halogen gains one electron
  from a metal
• Uses of Halogens
• Chlorine- disinfectant and bleach
• Bromine- dyes in cosmetics
• Iodine- hormone regulation
• Sublimation- a solid changes directly into a gas
  without first becoming a liquid

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Nonmetals- Cont.

• Noble Gases- exist as isolated, stable atoms
• Helium- used in blimps and balloons
• Neon, Argon, Krypton- used in lights

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Review Question

• C12 H22 O11
• Number of atoms
• C
• H
• O
• Total number of atoms________

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Mixed Groups

• Properties of Metalloids
• Form ionic and covalent bonds
• Have some metallic and some nonmetallic
  properties
• Partial conduction gives them semiconductor
  characteristics

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Mixed Groups- Cont.

• Boron Group- named for the first element in Group
  13
• Boron- use in water softening products,
  antiseptic, and fuels
• Aluminum- abundant in Earths crust used in
  cans, foil wrap, pans, building materials, and
  aircraft

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Mixed Groups- Cont.

• Carbon Group- four electrons in outer energy
  level
• Carbon- found in coal, oil, natural gas, and
  foods
• Silicon occurs as an allotrope- same element with
  different molecular structures
• Silicon- found in sand, rocks, and soil
• The main component in semiconductors, which
  conduct electricity under certain conditions
• Germanium- also used in semiconductors
• Tin- used to coat other metals
• Lead- toxic, so no longer used in paint
• Diamonds, graphite, and buckminsterfullerene are
  all allotropes of carbon.

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Mixed Groups- Cont.

• Nitrogen Group- five electrons in outer energy
  level trend to form covalent bonds
• Nitrogen- used to make nitrates and ammonia
• Phosphorus- used in water softeners, fertilizers,
  match heads, fine china
• Antimony and Bismuth- used with other metals to
  lower melting points

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Mixed Groups- Cont.

• Oxygen or Group 16
• Oxygen- makes up 20 of air, is used by living
  things in respiration, and provides protection
  from the suns radiation
• Sulfur- used to form sulfides for pigment in
  paint
• Selenium- used in photocopiers and multivitamines
• Te Po are also oxygen group elements.

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Mixed Groups- Cont.

• Synthetic elements- scientists create elements
  not usually found on Earth synthetic elements
  usually disintegrate quickly
• Uranium can be made into Neptunium which forms
  plutonium when it disintegrates
• Plutonium can be changed into Americum, which is
  used in smoke detectors.
• Transuranium have more than 92 protons and are
  synthetic and unstable
• The study of synthetic elements helps scientists
  to understand the forces holding the nucleus
  together.
• Element 114 lasted for 30 seconds.
• It combined 114 protons with 175 neutrons.
• It broke apart due to enormous repulsion between
  the protons.

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