Periodic Trends
Bonding
Lewis Structures
Molecular Geometry
100
What is the largest atom on the periodic table?
Francium (Fr)
100
What types of atoms make up a covalent bond?
Two nonmetals
100
What is the first step in drawing a Lewis structure?
Count valence electrons!!
100
What shape has bond angles of 109.5o?
Tetrahedral
200
What is effective nuclear charge?
The attractive pull that the positively charged nucleus has on the orbiting electrons.
200
With respects to energy, what happens when a bond breaks?
Input of energy is required break a bond (E>0)
200
What atoms can exceed the octet rule? Why?
Atoms in n=3 and beyond. These atoms have more energy levels that extra electrons can move into.
200
What shape has 6 atoms surrounding a central atom?
Octahedral
(Bonus points if you can explain why it's called an OCTAhedral if it has 6 outter atoms, not 8)
300
Which is larger, Li or Li+? Why?
Li is larger because Li+ has more protons in the nucleus, which pulls the orbiting electrons closer
300
Order the following from longest to shortest bond length: single bond, double bond, triple bond
single bond > double bond > triple bond
300
Draw the Lewis structure of water
300
What is the molecular geometry of CO2?
Linear
400
Arrange the following in order of decreasing electron affinity: C, Ne, Na, Si
C > Si > Na > Ne
(Ne is the lowest because it is a noble gas, so it has a stable octet and does not want any more electrons)
400
Which bond is least polar? Why?
O-C
O-Cl
O-H
Cl-H
O-Cl because the electronegativity difference between the two atoms is smallest
400
What is the formal charge on the central atom of NO3-? (might need to draw it)
-1
400
What is the molecular geometry of PH3? What is its electron geometry?
Molecular: Trigonal pyramidal
Electron: Tetrahedral
500
What is electronegativity, what directions does it increase on the periodic table, and why does it increase this way?
Electronegativity is the power of an atom in a molecule to attract electrons to itself. It increases as you go up a column because shielding of the electron orbitals around the nucleus decreases. It increases as you go to the right on a row because more protons have a stronger attractive force to electrons, and atoms get closer to reaching a stable, noble gas configuration.
500
How many sigma bonds and pi bonds are in the molecule?
18 sigma bonds
5 pi bonds
500
Draw the Lewis structure of PO43-. How many possible resonance structures are there?
4 possible resonance structures
500
Determine the shape and bond angles of SF4
Seesaw; Bond angles of <90o and <120o
