Quiz

QUIZ

1. Benzene is what type of solvent?

a. Polar and participatory b. Nonpolar and participatory c. Polar and non-participatory d. Nonpolar and non-participatory

Answer: d. Benzene is a nonpolar molecule because there are no major dipole moments. It does not add anything to the reactions, making it a non-participatory molecule.

2. Acetic acid is what type of solvent?

a. Polar and participatory b. Nonpolar and participatory c. Polar and non-participatory d. Nonpolar and non-participatory

Answer: a. Acetic acid is a polar molecule that is also an acid, making it a participatory molecule in the reactions that take place within it.

3. The dielectric constant will determine the polarity of a solvent. What is the

“cutoff” for a nonpolar versus polar solvent?

a. 1 b. 3 c. 5 d. 20

Answer: c. A dielectric constant of 5 or less is considered a nonpolar solvent.

4. What can be donated in a protic solvent?

a. H+ ion b. OH- ion c. NH4+ ion d. H20

Answer: a. A protic solvent is considered “protic” because it can donate a proton or H+ ion in an organic chemistry reaction.

5. Which solvent has the highest dielectric constant?

a. DMSO b. Acetic acid c. Ammonia d. Water

Answer: d. Water has the highest dielectric constant of 80—much higher than any other type of polar solvent.

6. Which type of solvent is most likely to be participatory in a chemical reaction?

a. Polar aprotic b. Polar protic c. Nonpolar protic d. Nonpolar aprotic

Answer: b. Polar protic solvents have the greatest ability to participate in chemical reactions by virtue of being able to donate a hydrogen ion to a reaction that takes place within it. It should therefore be included in the writing of most reactions as they are participatory.

7. Which solvent does not have a dipole moment of zero?

a. Toluene b. Benzene c. Pentane d. Hexane

Answer: a. Toluene has a slight dipole moment of 0.36, making it nonpolar; however, it does not have a dipole moment of zero, which is true of the other solvents.

8. Which solvent is most likely to have a density and specific gravity greater than water?

a. Toluene b. Pentane c. Chloroform d. Benzene

Answer: c. Each of these will be less dense than water except for the halogenated solvents, of which chloroform is one. Chloroform will not mix with water but will sit below it.

9. Which is the least polar solvent?

a. Acetone b. Ethanol c. Methanol d. Toluene

Answer: d. While there are different ways to determine the polarity of solvents, the dielectric constant is a good measure of polarity. The dielectric constant of toluene is much less than the dielectric constant of the other (polar) solvents.

10. Van der Waals bonding in solvation involves all but what kind of bonding interactions?

a. Dipole-dipole interactions b. Dipole-induced dipole interactions c. Ionic-ionic interactions d. Induced dipole-induced dipole interactions

Answer: c. Van der Waals bonding in solvation involves several types of interactions but it does not involve ionic-ionic interactions.