Chapter 6 (molecular compounds)

Question 1

Colavent bond

Answer 1

• a chemical bond in which one or more pairs of
  electrons are shared by two atoms
• full outer energy levels (and stability) are
  achieved by sharing valence electrons
• shared electrons are attracted to nuclei of
  both atoms… this holds the atoms together
• unlike an ionic bond, electrons are not
  transferred and atoms remain uncharged

Question 2

MULTIPLE COVALENT BONDS

Answer 2

• Double covalent bond
  involves sharing four
  electrons (two from
  each atom).
• Triple covalent bond
  involves sharing six
  electrons (three from
  each atom.

Question 3

MOLECULAR COMPOUND

Answer 3

• a compound formed when atoms of two or
  more elements share electrons
• composed of two or more nonmetals
• e.g. water, H2O – each of 2 hydrogen atoms
  forms a covalent with one oxygen atom by
  sharing electrons
• “covalent” = “molecular”
• exist as molecules

Question 4

MOLECULE

Answer 4

• the smallest unit of a pure substance that has
  two or more atoms covalently bonded (one or
  more shared pairs of electrons)
• not all molecules are compounds
  – compounds = 2 or more different elements
  VS.
  – molecules = 2 or more different or same elements
• e.g. oxygen molecule , O2 (not a compound)
• water molecule = water, H2O, compound

Question 5

Molecules

Answer 5

• molecule not compound, F2

Question 6

Diatomic Molecules

Answer 6

These seven elements occur naturally as
molecules containing two atoms.
HI BrONClF – hydrogen, iodine, bromine, oxygen,
nitrogen, chlorine, fluorine
HOFBrINCl the clown

Question 7

Properties of Covalent Compounds

Answer 7

• covalent bond is
  stronger than an
  ionic bond.
• attractions between
  molecules in a
  covalent compound
  are weaker than
  attractions between
  ions in ionic
  compounds
  (crystals)

Question 8

1) Physical State

Answer 8

• solid, liquid or gas
• soft
• low melting and
  boiling points
  because of weak
  attraction between
  molecules

Question 9

2) Solubility

Answer 9

• many do not
  dissolve in water
• e.g. small
  amounts of CO2
  (carbon dioxide)
  dissolve in water
  in soft drinks

Question 10

3) Conductivity

Answer 10

• poor conductors
  because they do not
  have free electrons
  or ions

Question 11

study

Answer 11

-Naming Molecular Compounds
-Naming covalent compounds
-Subscripts and Coefficients Give
Different Information