10 minutes maximum!

An IB Periodic Table is required.

1. The displayed formula for ethanol is:

ethanol molecule with angles

What are the approximate values of the H-C-H and C-O-H bond angles, labelled x and y?

  H-C-H angle (x) C-O-H angle (y)
A 90° 180°
B 90° 104.5°
C 109.5° 180°
D 109.5° 104.5°
2. Which statement is NOT true?
  • A.   CH4 has a tetrahedral shape
  • B.   NH3 is a non-polar molecule
  • C.   H3O+ has bond angles of approximately 107°
  • D.   NH4+ contains a coordinate bond
3. Which molecule is polar?
  • A.   CCl4
  • B.   BF3
  • C.   CO2
  • D.   PCl3
4. What is the best approximation of the C-N-H bond angle in methylamine, CH3NH2?
  • A.   107.0°
  • B.   109.5°
  • C.   120.0°
  • D.   180.0°
5. Which species has resonance structures?
  • A.   H3O+
  • B.   HCOOH
  • C.   CO32-
  • D.   CO2
6. The shapes of SO2 and SO3 are shown below:

SO3 and SO2 molecule shapes


Which row shows the correct polarity for these molecules?

  SO2 SO3
A polar polar
B polar Non-polar
C Non-polar polar
D Non-polar Non-polar
7. Which molecule has no net dipole moment?
  • A.   CCl4
  • B.   H2O
  • C.   NCl3
  • D.   HCl

8. Which species have delocalized electrons in their structure?

I. C6H6

II. NO3-


  • A.   I and II only
  • B.   I and III only
  • C.   II and III only
  • D.   I, II and III
9. Which pair of species has the same bond angles?
  • A.   NH3 and NH4+
  • B.   BeCl2and SCl2
  • C.   PH3 and H3O+
  • D.   CO2 and SO2
10. The Lewis structure for ozone, O3, is shown below:

Lewis structure for ozone


Which statement is NOT true for the ozone molecule?

  • A.   It contains a coordinate bond in its molecule
  • B.   It is a trigonal planar shape
  • C.   It has 2 oxygen-oxygen bonds of identical length
  • D.   It contains delocalized π electrons