Minutes

9

Seconds

59

 

Target: 10 Questions in 10 minutes

An IB Chemistry data booklet is helpful

1. Which of the following species has a resonance structure?

  • A.   H3O+
  • B.   HCOOH
  • C.   CO32-
  • D.   CO2

2. Which species have delocalized electrons in their structure?

I. C6H6
II. NO3-
III. CH3COO-
  • A.   I and II only
  • B.   I and III only
  • C.   II and III only
  • D.   I, II and III
3. The Lewis structure for ozone, O3, is shown here: Ozone lewis diagram

Which statement is NOT true for the ozone molecule?

  • A.   It contains a coordinate bond in its molecule
  • B.   It has a trigonal planar shape
  • C.   It has 2 oxygen-oxygen bonds of identical length
  • D.   It contains delocalized π electrons
4. What is the correct order of the carbon-oxygen bond length in methanol (CH3OH), methanoate ion (HCOO-) and carbonate ion (CO32-)?
  • A.   CH3OH < HCOO- < CO32-
  • B.   HCOO- < CO32- < CH3OH
  • C.   CO32- < CH3OH < HCOO-
  • D.   CO32- < HCOO- < CH3OH
5. Which of the following species does NOT show resonance?
  • A.   PO43-
  • B.   C6H5OH
  • C.   CH3COOH
  • D.   NO2-
6. In which of the following species do the S-O bonds have different lengths?
  • A.   H2SO4
  • B.   SO2
  • C.   SO3
  • D.   SO42-
7. What is the correct order of the nitrogen-oxygen bond length in NO3- , NO2+ and NO2- ?
  • A.   NO3- >NO2->NO2+
  • B.   NO2+ > NO3- >NO2-
  • C.   NO2- > NO3- >NO2+
  • D.   NO3- >NO2+>NO2-
8. Which of the following statements is NOT true for benzene?
  • A.   It has a H-C-C bond angle of 120o
  • B.   It has a planar shape
  • C.   It has a resonance structure.
  • D.   It has a C-C bond order of 1⅓
9 What is the best description of the bond lengths of the chlorine-oxygen bonds in the chlorate(VII) ion, ClO4- ?
  • A.   All four bonds are of the same length.
  • B.   All four bonds are of different lengths.
  • C.   There is one shorter bonds and three longer bonds.
  • D.  There are three shorter bonds and one longer bonds.

10. Which of the following statement are correct for the delocalized electrons in benzene?

I. The electrons are delocalized in a π system formed from overlapping p orbitals on each C atom.
II. The delocalization of electrons gives benzene extra stability, in comparison to a structure with three double and three single carbon-carbon bonds (the Kekulé structure).
III. There are 12 delocalized electrons per benzene molecule.
  • A.   I and II only
  • B.   I and III only
  • C.   II and III only
  • D.   I, II and III