Bond Properties
Lewis Structures
Molecular Shapes
Ionic Bonds
This & That
100
What happens to the strength of a bond as the number of shared electrons increases?
Bond strength increases
100
What rule should be followed if at all possible when drawing Lewis Structures?
Octet rule
100
What are two types of molecular shapes where all the atoms lie in a single plane?
linear, trigonal planar, bent
100
How many electrons will aluminum lose when it becomes an ion?
3
100
How do you determine the formal change on an atom in a Lewis structure?
see how many electrons it is contributing in the Lewis structure compared to how many valence electrons it has.
200
Which of the following diatomic molecules contains a double bond?
N2, Br2, O2, Cl2, H2
O2
200
How many valence electrons are used to make the Lewis structure for PO4-3?
32 valence electrons
200
What is the molecular shape of NH3?
trigonal pyramidal
200
Which of the following compounds will have the most ionic character to its bond?
KCl, LiF, NaCl, KF, LiCl
KF
200
What is a dipole moment?
unequal charge distribution due to unequal sharing of electrons
300
Describe how covalent bonds differ from ionic bonds. Give an example of a covalent compound and an ionic compound.
Ionic bonds transfer electrons to reach a stable octet. Ex: NaCl
Covalent bonds share electrons to reach a stable octet. Ex: CH4
300
What are the formal charges on each atom in the nitrite (NO2-1) ion?
Nitrogen = 0
Oxygen = -1, 0
300
What is the molecular shape of a molecule with 4 areas of electrons and 2 of them are lone pairs?
Bent
300
What is the approximate difference in electronegativity needed in order for a bond to be considered nonpolar?
less than 0.5
300
How many valence electrons do each of the following atoms have?
Carbon
Gallium
Bromine
Sodium
Carbon = 4
Gallium =3
Bromine =7
Sodium= 1
400
What is the difference between a polar covalent bond and a nonpolar covalent bond?
Polar covalent bonds have unequal sharing of the electrons. This sets up a partial positive and a partial negative end..poles. Nonpolar covalent bonds share electrons equally. There are no partial charges created in the molecule.
400
Which one of the following particles would have a Lewis structure most like that of carbon disulfide, CS2? What is the shape of the molecule?
NO2, NO2-1, NO2+1
NO2+1
linear
400
What is the shape of a SO3 molecule?
trigonal planar
400
How could you experimentally determine if a soluble compound contains an ionic or covalent bond?
dissolve it in water and test its conductivity. If it is ionic, it will conduct electricity. If it is covalent, it won't.
400
Name the 5 shapes molecules can obtain when there are no lone pairs on the central atom.
linear, trigonal planar, tetrahedral, trigonal bipyramidal, octahedral
500
Which if the most polar bond?
Cl-F
F-F
C-F
N-F
O-F
C-F
500
Draw two possible Lewis structures for SCN-1?
500
Group the following ions into pairs based on their shape. Identify the shape of each pair.
SO3-2, NO3-1, CO3-2, PO3-3
SO3-2 and PO3-3 = trigonal pyramidal
NO3-1 and CO3-2= trigonal planar
500
Name 5 characteristics of ionic bonds?
1. metal + nonmetal
2. High electronegativity difference
3. Soluble in water
4. high melting point
5. transfers electrons
500
1. What is the difference between electron affinity and ionization energy?
2. Which elements have the highest ionization energy?
3. Which elements have the highest electron affinity?
1. ionization energy is the energy is takes to remove an electron. Electron affinity is the energy change accompanied by the addition of an electron
2. noble gases
3. halogens