Exam 3

Question 1

Identify the colligative property.            

1. freezing point depression
2. vapor pressure lowering
3. osmotic pressure
4. boiling point elevation
5. all of the above

Question 2

A solution is prepared by dissolving 7.00 g of glycerin (C 3H 😯 3) in 201 g of ethanol    The freezing point of the solution is ________°C. The freezing point of pure ethanol is    at 1 atm. The molal-freezing-point-depression constant (K f) for ethanol is    The molar masses of glycerin and of ethanol are 92.1 g/mol and 46.1 g/mol, respectively.      

1.  -115.4
2. 0.752
3. -107.9
4. -121.3
5. -113.8

Question 3

Calculate the freezing point of a solution of 40.0 g methyl salicylate, C 7H 6O 2, dissolved in 800. g of benzene, C 6H 6.    and the freezing point is 5.50°C for benzene.        

1.  3.41°C
2. 7.59°C
3. 2.09°C
4. -2.09°C

Question 4

Which of the following statements is TRUE?    

1. In general, the solubility of a solid in water decreases with increasing temperature.
2. The solubility of a gas in water usually increases with decreasing pressure.
3. In general, the solubility of a gas in water decreases with increasing temperature.
4. The solubility of an ionic solid in water decreases with increasing temperature.
5. None of the above statements are true.

Question 5

Identify the type of solid for gold.          

1.  nonbonding atomic solid
2. molecular solid
3. networking atomic solid
4. ionic solid
5. metallic atomic solid

Question 6

Identify the type of solid for diamond.           

1. networking atomic solid
2. ionic solid
3. metallic atomic solid
4. nonbonding atomic solid
5. molecular solid

Question 7 

Why is water an extraordinary substance?            

1. Water has an exceptionally high specific heat capacity.
2. Water has a low molar mass, yet it is a liquid at room temperature.
3. Water is the main solvent within living organisms.
4. Water has strong hydrogen bonding.
5. All of the above.

Question 8

List an ingredient that is in antacid.          

1.  Mg(OH)2
2. Al(OH)3
3. CaCO3
4. all of the above
5. none of the above

Question 9

Which of the following is a Br  nsted-Lowry base?          

1. Cl2
2. CH4
3. HCN
4. NH3
5. None of the above are Br nsted-Lowry bases.

Question 10

Which of the following statements is TRUE?          

1. A strong acid has a strong conjugate base.
2. A strong acid is composed of a proton and an anion that have a very strong attraction for one another.
3. The conjugate base of a very weak acid is stronger than the conjugate base of a strong acid. 
4. A weak base is composed of a cation and an anion with a very weak attraction between them.
5. None of the above statements are true.