Week # 8 Review AP Chem

The Lewis structure of N₂H₂ shows __________.

• a nitrogen-nitrogen triple bond

• 
  each nitrogen has one lone pair

• 
  each hydrogen has one lone pair

• a nitrogen-nitrogen single bond

• 
  each nitrogen has two lone pairs

In the nitrite ion (NO₂^-), __________.

• 
  both bonds are single bonds

• 
  both bonds are the same because of resonance

• 
  both bonds are double bonds

• there are 20 valence electrons

• 
  there is one single and one double bond

The ability of an atom in a molecule to attract electrons is best quantified by the ______.

• 
  electronegativity

• diamagnetism

• 
  

  paramagnetism

• 
  

  electron change-to-mass ratio

• 
  first ionization energy

A valid Lewis structure of _______ cannot be drawn without violating the octet rule.

• 
  NF₃

• PF₃

• IF₃

• 
  SbF₃

• 
  SO₄^2-

Which atom can accommodate an octet of electrons, but doesn't necessarily have to accommodate an octet?

• 
  N

• 
  H

• 
  B

• C

• O

In the resonance form of ozone shown, the formal charge on the central oxygen atom is _______.

• 0

• -1

• 
  -2

• 
  +1

• 
  +2

Bond enthalpy is __________.

• 
  always negative

• 
  sometimes positive and sometimes negative

• 
  unpredictable

• 
  always zero

• always positive

As the number of covalent bonds between two atoms increases, the distance between the atoms ______ and the strength of the bond between them ______.

• 
  increases, increases

• increases, decreases

• 
  is unpredictable

• 
  decreases, decreases

• 
  decreases, increases

The Lewis structure of the CO₃^2- ion is

• 
• 
• 
• 
• 

Which of these bonds takes the most energy to break?

• single

• double

• triple

• quadruple