intermolecular forces in class assignment.notebook
October 16, 2014
A. Multiple Choice. Indicate the correct response on the Scantron card provided.
1. Hydrogen bonding can occur between water molecules and which other substance:
a) Carbon tetrachloride
b) carbon dioxide
c) Ammonia
d) sodium fluoride
2. Propane, CH3CH2CH3 has a lower melting point than butane, CH3CH2CH2CH3 because:
a) Propane is a more polar molecule than butane.
b) Butane has more hydrogens therefore stronger hydrogen bonding.
c) Propane has fewer atoms and therefore fewer electrons than butane.
d) Butane has weaker London dispersion forces than propane.
3. The VSEPR shape of silicon tetrahydride would be:
a) tetrahedral
b) trigonal planar
c) trigonal pyramidal
d) linear
4. Intermolecular forces:
a) involve the sharing of electrons between atoms
b) are stronger than ionic bonds
c) do not exist between nonpolar molecules
d) can determine the physical state of a substance at room temperature
5. Polar compounds have higher boiling points than nonpolar compounds because:
a) polar molecules are held loosely together and it takes little energy to separate them
b) nonpolar molecules have high attractive forces due to the motion of electrons
c) attraction between oppositely­charged poles holds molecules closer together
d) nonpolar molecules are made up entirely of nonpolar bonds.
Oct 16­8:18 AM
6. The molecule which would form a trigonal planar shape would be:
a) CH3Cl
b) SiOF2
c) NH3
d) PF4
7. All diatomics exhibit the following intermolecular forces:
a) London dispersion forces b) London dispersion forces (negligible) and dipole­dipole forces
c) London dispersion forces (negligible) and hydrogen bonding
c) none of the above
8. Which of the following molecules is polar?
a) C2I2
b) COH2 c) C2F4
d) SiCl4
9. Which of the following molecules forms a trigonal pyramidal shape?
a) HCSBr b) C2F2 c) SF2
d) PF3
10. The correct chemical name for CuCO3 is:
a) copper (II) carbonate b) cuprous carbonate
d) copper carbonate
c) copper (I) carbon trioxide
Oct 16­8:21 AM
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intermolecular forces in class assignment.notebook
October 16, 2014
11. The correct chemical formula for nitrous acid is:
a) HNO3
b) HNO2
c) H2N d) H2NO2
12. The bond between a carbon and a chlorine would be classified as a:
a) nonpolar covalent bond
b) polar covalent bond
c) ionic bond
d) double covalent bond
13. For a molecule of carbon tetrafluoride, the following statement is correct:
a) All bonds within the molecule are polar, therefore the overall molecule is polar
b) The electrons shared between the carbon and fluorine atoms are shared equally.
c) All bonds within the molecule are polar, therefore the overall molecule is polar
d) The electrons shared between the carbon and fluorine atoms are located closer to the fluorine atoms.
14. Which of the following molecules would exhibit hydrogen bonding?
a) CH3F b) NH3 c) OF2
d) PH2F
15. Which of the following substances is most likely to be soluble in water?
a) CH4
b) Si2Br4
c) CH3Cl
d) CS2
Oct 16­8:25 AM
16. Carbon tetrachloride does not dissolve in water because:
a) Water molecules are more attracted to each other than to CCl4 molecules
b) CCl4 molecules are highly attracted to each other and therefore will not separate
c) Both molecules exhibit hydrogen bonding and therefore cannot form a solution.
d) CCl4 molecules are too large to dissolve in water.
17. One could predict OS2 to have a higher boiling point than S2 because:
a) OS2 has more electrons than S2
b) OS2 has a higher ∆EN than S2
c) OS2 is a polar molecule, whereas S2 is nonpolar
d) S2 has stronger dipole­dipole forces than OS2
18. Induced dipoles occur in the following molecules:
a) polar molecules only
b) polar molecules in which hydrogen is bonded to nitrogen, oxygen or fluorine
c) nonpolar molecules only
d) all molecules
19. Hydrogen bonding will be strongest in which of the following molecules:
a) NH3 b) H2O c) CH3OHd) OF2
20.
a)
b)
c)
d)
In comparing N2H4 and C2H4, which of the following statements is true?
N2H4 has the higher boiling point as it has hydrogen bonding whereas C2H4 does not.
Both are nonpolar molecules. N2H4 has the higher boiling point because it has more electrons.
C2H4 has the higher melting point as it has a higher ∆EN than N2H4.
C2H4 has the higher melting point as it has higher dipole­dipole forces whereas N2H4 has only London dispersion forces.
Oct 16­8:27 AM
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intermolecular forces in class assignment.notebook
October 16, 2014
Oct 16­8:44 AM
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intermolecular forces in class assignment.notebook
October 16, 2014
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intermolecular forces in class assignment.notebook
October 16, 2014
Homework: Unit Project
(FINISH!!!)
Oct 16­8:44 AM
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