AP Chemistry Unit 2 Review

The following molecules all contain polar bonds however only one is a polar molecule.  Which one?

• CCl₄

• CO₂

• NH₃

• CH₄

Determine the electron geometry (eg) and molecular geometry (mg) of XeF4 (Lewis structure is shown) .

• eg = tetrahedral, mg = tetrahedral

• eg = linear, mg = linear

• eg = octahedral, mg = square planar

• eg = trigonal bipyramidal, mg = tetrahedral

What is the VSPER shape of PCl₅

• See-saw

• trigonal planar

• octahedral

• trigonal bipyramidal

Which of the following molecular shapes would have a bond angle of 180 Degrees?

• Bent

• Trigonal Planar

• Tetrahedral

• Linear

Which of these alloys is a substitutional alloy?

• Bronze

• Steel

Why is the bond angle in NH₃ molecule is smaller than that in CH₄ molecule?

• Among the four electron pairs around the central atom N in NH₃

  molecule, there are two lone pairs which require more space than bonding pairs and tend to compress the angles between the bonding pairs.

• Among the four electron pairs around the central atom N in NH₃

  molecule, there is one lone pair which requires more space than a bonding pair and tends to compress the angles between the bonding pairs.

• Among the four electron pairs around the central atom N in NH₃

  molecule, there is one lone pair which requires less space than bonding pairs and tend to increase the angles between the bonding pairs.

• In reality, bond angle in NH₃ molecule is larger than that in CH₄ molecule.

Choose the correct Electron Geometry and then Molecular Geometry of this molecule.

• Tetrahedral, Trigonal planar

• Tetrahedral, Trigonal pyramidal

• Tetrahedral, Tetrahedral

• Trigonal Bipyramidal, Bent

Which structure consists of a giant lattice of cations and anions held together by strong electrostatic forces of attraction?

• ionic bonding

• metallic bonding

• covalent bonding

Ionic Compounds are normally Solid at Room Temperature and known as Salts. The lattice energy of a salt is related to the energy required to separate the ions of solid ionic s. For which of the following pairs of ions is the energy that is required to separate the ions largest?

• K and F

• Fr and I

• Ga and O

• Al and O

What type of alloy is made when the radii of the atoms are similar in size?

• interstitial

• substitutional