10 minutes maximum!

An IB Periodic Table is required.

1. Which is the correct Lewis (electron dot) structure for the PCl3 molecule?

Lewis diagram for PCl3

2. What is the total number of valence electrons in the ethanoate ion, CH3CO2- ?

  • A.   14
  • B.   23
  • C.   24
  • D.   32
3. Which species is trigonal planar in shape?
  • A.   PH3
  • B.   CCl4
  • C.   BF3
  • D.   H3O+
4. How many electron domains are on the carbon atom in carbon dioxide, CO2?
  • A.   2
  • B.   4
  • C.   6
  • D.   8
5. What is the shape of the ammonia, NH3, molecule?
  • A.   tetrahedral
  • B.   trigonal pyramidal
  • C.   trigonal planar
  • D.  linear

6. Which row shows the correct electron domain geometry and molecular geometry for the NH2- ion?

  Electron domain geometry Molecular geometry
A trigonal planar bent V-shaped
B trigonal planar linear
C tetrahedral linear
D tetrahedral bent V-shaped
7. Which statement is NOT true for the H3O+ ion?
  • A.   The oxygen atom has 3 electron domains
  • B.   It has a coordinate bond in its structure
  • C.   It has a trigonal pyramidal  shape
  • D.   The H-O-H bond angles are approximately 107°
8. What is the shape of the carbonate ion, CO32-?
  • A.   tetrahedral
  • B.   trigonal pyramidal
  • C.   trigonal planar
  • D.  bent V-shaped

Q9-10
These questions concern sulfur fluoride, SF2.

9. Which is the correct Lewis (electron dot) structure for SF2?

  
lewis diagram SF2

10. What is the correct molecular shape for SF2 and will the molecule be polar or non-polar?

  Molecular Shape Polarity
A linear polar
B linear non-polar
C bent V-shape polar
D bent V-shape non-polar