ionic has a higher boiling and melting point; molecular has a lowr boiling and melting point
How do ionic compounds and molecular compounds differ in their relative melting and boiling points?
number, kinds, and arrangements
What information does a moecule's molecular structure give?
109.5
What is the bond angle of tetrahedral?
120
What is the bond angle of trigonal planar?
- greater than 2.0 = ionic
- 1.9-.5 = polar covelent
-0-.4 = non polar covelent
Electronegativity difference between bonded atoms chart.
hybridization
the mixing of several atoic orbitals to form th same nmber oquivalent hybrid orbitals
resonance structures
two or more valid electron dot formulas that can be written for the same molecules
structural formula
chemical formula that shows the arrangemet of atoms in molecules nd polyatomic ions
van der Waals forces
the weakest attractions that exist between molecules
VSEPR theory
Because electron pairs repel, molecules adjust their shapes so that the valence electron pairs are as far apart as possible
Valence-shell-electron-pair-repulsion
What does VSEPR stand for?
single covelent bond
a covalent bond in which one pair of electrons is shared between two atoms
polar molecules
a molecule in which one end is slightly negative and the other end is slighly positive
polar covalent bonds
a covalent bond formed between two different atoms in which the bonding electrons are shared unequally
molecular compound
an electrically neugtral group of atoms joined together by covalent bonds
coordinate covalent bonds
a covalent bond in which one atom contributes bth bonding electrons
C. Cl
Which of the following exists as a diatomic molecule?
a. He ; b. Ar ; c. Cl ; d. Na
a. F?
The diatomic molecule among the following that contains a single covalent bond is
a. F?; b. O?; c. N?; d. O?-
d. noble gases
Atoms share electrons in order to acquire te electron configurations of
a. alkali metals ; b. alkaline earth metals ; c. halogens ; d. noble gases
d. N?
The diatmic mlecule among the following that contins a triple covalent bond is
a. o?; b. Cl?; c. H?; d. N?
b. NH?
The covalent molecule among the following is
a. NaCl ; b. NH?; c.HI ; d. H?O
d. Cl
In forming the molecule HF,the F atoms attains the electron configuration of
a. He ; b. Ne ; c. Ar ; d. Cl
c. O?(ozone)
The molecule among the folloing tha exhibits resonance structures is
a. CO?; b. CH?; c. O?(ozone) ; d. NH?
b. hybrids
Resonance sructures are considered
a. polar molecles ; b. hybrids; c. coordinate covalent molecules ; d. none of the above
b. paramagnetic
Substancs that show relatively strong attractions to an external megneti field are said to be
a. diamagnetic ; b. paramagnetic ; c. nonmagnetic ; d. none of the above
b. paramagnetic
Oxygen is an example of a substance that is
a. diamagnetic ; b. paramagnetic ; c. nonmagnetic ; d. none of the above
c. sigma bond
When 2 atomc orbitals combine to form a molecular orbital that is symmetrical along the axis onnecting the two atomic nuclei, the bond that is produced is referred to as a(n)
a. ionic bond ; b. pi bond ; c sigma bond ; d. none of the above
b. pyramidal
The shape of a molecule of NH? is said to be
a. tetrahedral ; b. pyramidel ; c. bent ; d. linear
c. one sp? hybrid orbital
In a methane (CH?) molecule, the mixingof one 2s orbtal with three 2p orbitals form
a.one sp? hybrid orbital ; b. four sp hybrid orbitals ; c. one sp?hybrid orbital ; d. four sp? hybrid orbitals
b. pi bonds
The overlap of atomic s orbitals produces a(n)
a ionic bonds ; b. pi bonds ; c. sigma bonds ; d. none of the above
c. are extremely hard
Network solids
a. have low melting points ; b. have low boiling points ; c. are extremely hard ; d. are extremely ductile