Lecture2'2: Chemical Bonding

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Lecture-2.2 Chemical Bonding
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Chemical Bonding

• Recall...
• ... an element is a pure form of matter that is
  composed of atoms all of which have the same
  atomic number (number of protons).
• Recall...
• ... a compound is a pure form of matter that is
  composed of atoms of two or more different
  elements in a set or definite ratio.
• So what holds the atoms together in elements and
  compound?

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Chemical Bonding

• What holds the atoms together in iron?

Fe
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Chemical Bonding

• What holds the atoms together in zinc?

Zn
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Chemical Bonding

• What holds the atoms together in iodine?

I2
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Chemical Bonding

• What holds the atoms together in sulfur?

S
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Chemical Bonding

• What holds the atoms together in sucrose?

C12H22O11
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Chemical Bonding

• What holds the atoms together in water?

H2O
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Chemical Bonding

• The atoms in elements and compounds are held
  together by chemical bonds.
• A chemical bond is a strong force of attraction
  that exists between atoms in elements and
  compounds.
• But what is it that actually does the attracting?

How you doing?
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Chemical Bonding

• All chemical bonding involves ELECTRONS!
• In some bonding, electrons are transferred
• In some bonding, electrons are shared.
• In some bonding, electrons are transferred and
  then shared.
• When bonding, atoms will transfer electrons,
  share electrons, or transfer and then share
  electrons in order to get a full valence of
  electrons.
• A full valence of electrons is a stable state.

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Chemical Bonding

• There are three different types of chemical
  bonding
• ionic bonding
• covalent bonding
• metallic bonding
• Ionic bonding occurs between atoms of metallic
  and nonmetallic elements.
• Covalent bonding occurs between atoms of
  nonmetallic elements.
• Metallic bonding occurs between atoms of metallic
  elements.

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Chemical Bonding

• The atoms in NaCl are held together by ionic
  bonding.
• NaCl

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Chemical Bonding

• The atoms in C12H22O11 are held together by
  covalent bonding.
• C12H22O11

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Chemical Bonding

• The atoms in aluminum foil are held together by
  metallic bonding.
• Al

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Chemical Bonding

• The atoms in bronze, an alloy of Cu and Sn, are
  held together by metallic bonding.
• Cu and Sn

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Chemical Bonding

• The atoms in NaOH are held together by both ionic
  and covalent bonding.
• NaOH

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Chemical Bonding

• When a formula has a metal and then two or more
  nonmetal elements, the atoms are held together by
  both ionic and covalent bonding.

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Chemical Bonding

• Ex.1) What type (or types) of bonding is found
  in a sample of super melt (CaCl2)?
• Theres a metallic and a nonmetallic element.
• Ionic bonding!

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Chemical Bonding

• Ex.2) What type (or types) of bonding is found
  in a sample of rubbing alcohol (C3H6O)?
• There are ONLY nonmetallic elements.
• Covalent bonding!

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Chemical Bonding

• Ex.3) What type (or types) of bonding is found
  in a sample of sterling silver (Ag and Cu)?
• There are ONLY metallic elements.
• Metallic bonding!

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Chemical Bonding

• Ex.4) What type (or types) of bonding is found
  in a sample of iodine (I2)?
• Theres ONLY a nonmetallic element.
• Covalent bonding!

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Chemical Bonding

• Ex.5) What type (or types) of bonding is found
  in a sample of iron rust (Fe2O3)?
• Theres a metallic and a nonmetallic element.
• Ionic bonding!

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Chemical Bonding

• Ex.6) What type (or types) of bonding is found
  in a sample of baking soda (NaHCO3)?
• Theres a metallic element and
  three nonmetallic elements.
• Both ionic and covalent bonding!

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Chemical Bonding

• Ex.7) What type (or types) of bonding is found
  in a sample of diamond (C)?
• Theres ONLY a nonmetallic element.
• Covalent bonding!

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Chemical Bonding

• Ex.8) What type (or types) of bonding is found
  in a sample of magnesium (Mg)?
• Theres ONLY a metallic element.
• Metallic bonding!

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Chemical Bonding

• Ex.9) What type (or types) of bonding is found
  in a sample of silver tarnish (Ag2S)?
• Theres a metallic and a nonmetallic element.
• Ionic bonding!

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Chemical Bonding

• Ex.10) What type (or types) of bonding is found
  in a sample of saltpeter (KNO3)?
• Theres a metallic element and two nonmetallic
  elements.
• Both ionic and covalent bonding!

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Chemical Bonding

• Ex.11) What type (or types) of bonding is found
  in a sample of solder (Pb and Sn)?
• There are ONLY metallic elements.
• Metallic bonding!

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Chemical Bonding

• Ex.12) What type (or types) of bonding is found
  in a sample of aspirin (C9H8O4)?
• There are ONLY nonmetallic elements.
• Covalent bonding!

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Chemical Bonding

• Ex.13) What type (or types) of bonding is found
  in a sample of lye soap (NaC18H35O2)?
• Theres a metallic element and
  three nonmetallic elements.
• Both ionic and covalent bonding!

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Chemical Bonding

• Ex.14) What type (or types) of bonding is found
  in a sample of pyrite (FeS2)?
• Theres a metallic and a nonmetallic element.
• Ionic bonding!

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Chemical Bonding

• Ex.15) What type (or types) of bonding is found
  in a sample of copper pipe (Cu)?
• Theres ONLY a metallic element.
• Metallic bonding!

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Chemical Bonding

• Ex.16) What type (or types) of bonding is found
  in a sample of Epsom salts (MgSO4)?
• Theres a metallic element and two nonmetallic
  elements.
• Both ionic and covalent bonding!

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Chemical Bonding

• Ex.17) What type (or types) of bonding is found
  in a sample of butane (C4H10)?
• There are ONLY nonmetallic elements.
• Covalent bonding!

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Chemical Bonding

• Ex.18) What type (or types) of bonding is found
  in a sample of titanium (Ti)?
• Theres ONLY a metallic element.
• Metallic bonding!

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Chemical Bonding

• Ex.19) What type (or types) of bonding is found
  in a sample of caustic lime (CaO)?
• Theres a metallic and a nonmetallic element.
• Ionic bonding!

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Chemical Bonding

• Ex.20) What type (or types) of bonding is found
  in a sample of bleach (NaClO)?
• Theres a metallic element and two nonmetallic
  elements.
• Both ionic and covalent bonding!