Lewis Diagrams (College Board AP® Chemistry): Exam Questions

50 mins20 questions
1
1 mark

Nitrous acid (HNO2) is produced when nitrogen dioxide dissolves in water to produce acid rain. What is the correct Lewis diagram for nitrous acid?

  • AP chemistry Lewis diagram HNO2 option A
  • AP chemistry Lewis diagram HNO2 option B
  • AP chemistry Lewis diagram HNO2 option C
  • AP chemistry Lewis diagram HNO2 option d
2
1 mark

Which of the species shown below does not have resonance structures?

  • benzene (C6H6)

  • carbonate ion (CO32-)

  • ethene (C2H4)

  • ozone (O3)

3
1 mark

Which of the following compounds contains an atom that does not obey the octet rule?

  • CCl4

  • PCl3

  • NO3-

  • ClF3

4
1 mark

Which compound contains an atom that does not obey the octet rule?

  • BF4-

  • SCl4

  • CS2

  • NOCl

5
1 mark

What is the correct formula to work out the formal charge on an atom?

  • FC = (number of valence electrons) - 1 half(number of bonding electrons) - (number of non-bonding electrons)

  • FC = (number of valence electrons) + (number of bonding electrons) + (number of non-bonding electrons)

  • FC = (number of valence electrons) - (number of non-bonding electrons) - (number of bonding electrons)

  • FC = (number of valence electrons) - 1 half(number of non-bonding electrons) - (number of bonding electrons)

1
1 mark
HPO42- ion

What is the formal charge on atom 1 in the hydrogen phosphate ion, HPO42-?

  • 0

  • -1

  • -2

  • 1

2
1 mark
HPO42- ion

What is the formal charge on atom 2 in the hydrogen phosphate ion, HPO42-?

  • 0

  • -1

  • -2

  • 1

3
1 mark
A Lewis diagram of a hydrogenphosphate ion

What is the formal charge on atom 3 in the hydrogen phosphate ion, HPO42-?

  • 0

  • -1

  • -2

  • 1

4
1 mark

How many lone pairs of electrons exist on I3-?

  • 3

  • 5

  • 7

  • 9

5
1 mark

Carbon dioxide can be represented by at least two resonance structures, I and II.

Lewis structures of carbon dioxide

The formal charges on the oxygen atoms are

Structure I

Structure II

1

2

1

2

A

+1

+1

0

+1

B

-1

0

-1

-1

C

0

0

+1

-1

D

+1

0

0

-1

    1
    1 mark

    Which of the following statements are true for XeO3?

    1. Has a trigonal pyramidal shape

    2. One possible Lewis structure has two oxygen atoms with a formal charge of -1

    3. Xenon has a formal charge of +2 in one possible Lewis structure

    • I and II only

    • I and III only  

    • II and III only 

    •  I, II and III

    2
    1 mark

    The nitrate(V) ion, NO3-, is a polyatomic ion, bonded by covalent bonds.

    Which of the following shows the correct displayed formula for the nitrate ion?

    q9-4-1_hard_mcq_ib-chemistry-sl