UNE 1011 midterm Exam Questions And
Already Passed Answers.
Strong electrolytes:
a.dissociate almost completely into ions in solution
b. only yield a small fraction of ions in solution
c. are always dissolved ionic compound
d. Can not be covalent compounds - Answer a. dissociate almost completely into ions in
solution
Hexane is commonly used in labs as solvent for non polar compounds. what is the molality of
22.3 mg of vitamin D (C27H44O, 384.6 g/mol) in 50 mL of hexane? Hexane has a density of
0.661 g/mol - Answer 1.75 X 10^-3 m
A foam is a collie composed of - Answer a gas dispersed in a liquid
the solubility of a solid in a liquid typically _____ (increases/decreases) with ______
(increasing/decreasing) temperatures with a few exceptions. - Answer typically increases with
increasing temperatures
when a solute is introduced to a solvent:
a. energy is released by forming solute-solute and solvent-solvent interactions
b.a solution will always form
c. energy is released when solute-solvent interactions are formed
d. a solution will only form if energy released by salvation is low - Answer c. energy is released
when solute-solvent interactions are formed
Which of the following will have the lowest freezing point:
a. 0.1 M NaCl in water
b. 0.5 M NaCl in water
c. 1.0 M NaCl in water
d. 2.0 M NaCl in water - Answer d. 2.0 M NaCl in water
,a. 0.1 M potassium chloride KCl
b. 0.1 M sodium sulfate Na2SO4
c. 0.1 M calcium nitrate Ca(Na3)2
d. 0.1 M sucrose, C12H22O11 - Answer d. 0.1 M sucrose C12H22O11
true or false: many soap or detergent molecules surround non polar substances to form collide
particles that can easily be washed away - Answer true
The pressure of carbon dioxide in a bottle of sparkling water is 2.50 atm at 25 degrees C. What
mass of CO2 is dissolved in a 0.5L bottle of sparkling water? The Henrys law constant for CO2 in
water is 3.3 X 10^-2 mol/LXatm - Answer 1.8g
in the reaction 3H2(g) + N2(g) --> 2NH3(g) the instantaneous rate of consumption for H2 during
an experiment is determined to be 5.76 X 10^-3 molL^-1. What is the instantaneous rate of
production of NH3? - Answer 3.84 X 10^-3 mol L^-1 min^-1
an integrated rate law describes - Answer the relationship between the initial concentration of
reactants and the concentration of reactants at a specific time
The reaction rate that is calculated at any specified time while the reaction is proceeding is the
___ - Answer instantaneous rate
Reactant vs time positive slope going up diagonal slope= k. What order type of reaction is this -
Answer second order
Arrange each solution from lowest to highest freezing point assuming each solution has a
volume of 100 mL
1. pure water
2. water with 1 teaspoon of dissolved sugar
3. water with 2 teaspoons of dissolved sugar
4. water with 1/2 teaspoon of dissolved sugar - Answer 3,2,4,1
T/F: a 5.0% NaCl solution has a lower freezing point than a 2.0% NaCl solution - Answer true
, T/F: a 5.0 sucrose solution has a higher boiling point than pure water - Answer true
T/F: a 2.0% NaCl solution has a higher vapor pressure than pure water - Answer false
T/F: A 5.0% sucrose solution has a higher osmotic pressure than a 10% sucrose solution -
Answer false
osmosis - Answer solvent in a less concentrated solution passes through a membrane into a
more concentrated solution
has an inversely proportional relationship with temperature - Answer concentration of the
solution
has a proportional relationship with temperature - Answer osmotic pressure
allows only certain particles to pass through - Answer semipermeable membrane
______ is/are needed to stop the movement of solvent through a membrane - Answer
osmotic pressure
T/F: colligative properties (freezing point depression, boiling point elevation, and osmotic
pressure) have been used to determine the molar mass of a solute - Answer true
When osmotic pressure is kept constant, the relationship between molarity(M) and
temperature (T) is ____ - Answer inversely proportional
T/F: a solution that contains a solvent and non-volatile solute particles has a lower vapor
pressure than a pure solvent under the same conditions - Answer True
what are the 4 colligative properties of a solution - Answer vapor pressure lowering, freezing
point depression, boiling point elevation, and osmotic pressure
The temperature at which the vapor pressure of a liquid is equal to the atmospheric pressure on
Already Passed Answers.
Strong electrolytes:
a.dissociate almost completely into ions in solution
b. only yield a small fraction of ions in solution
c. are always dissolved ionic compound
d. Can not be covalent compounds - Answer a. dissociate almost completely into ions in
solution
Hexane is commonly used in labs as solvent for non polar compounds. what is the molality of
22.3 mg of vitamin D (C27H44O, 384.6 g/mol) in 50 mL of hexane? Hexane has a density of
0.661 g/mol - Answer 1.75 X 10^-3 m
A foam is a collie composed of - Answer a gas dispersed in a liquid
the solubility of a solid in a liquid typically _____ (increases/decreases) with ______
(increasing/decreasing) temperatures with a few exceptions. - Answer typically increases with
increasing temperatures
when a solute is introduced to a solvent:
a. energy is released by forming solute-solute and solvent-solvent interactions
b.a solution will always form
c. energy is released when solute-solvent interactions are formed
d. a solution will only form if energy released by salvation is low - Answer c. energy is released
when solute-solvent interactions are formed
Which of the following will have the lowest freezing point:
a. 0.1 M NaCl in water
b. 0.5 M NaCl in water
c. 1.0 M NaCl in water
d. 2.0 M NaCl in water - Answer d. 2.0 M NaCl in water
,a. 0.1 M potassium chloride KCl
b. 0.1 M sodium sulfate Na2SO4
c. 0.1 M calcium nitrate Ca(Na3)2
d. 0.1 M sucrose, C12H22O11 - Answer d. 0.1 M sucrose C12H22O11
true or false: many soap or detergent molecules surround non polar substances to form collide
particles that can easily be washed away - Answer true
The pressure of carbon dioxide in a bottle of sparkling water is 2.50 atm at 25 degrees C. What
mass of CO2 is dissolved in a 0.5L bottle of sparkling water? The Henrys law constant for CO2 in
water is 3.3 X 10^-2 mol/LXatm - Answer 1.8g
in the reaction 3H2(g) + N2(g) --> 2NH3(g) the instantaneous rate of consumption for H2 during
an experiment is determined to be 5.76 X 10^-3 molL^-1. What is the instantaneous rate of
production of NH3? - Answer 3.84 X 10^-3 mol L^-1 min^-1
an integrated rate law describes - Answer the relationship between the initial concentration of
reactants and the concentration of reactants at a specific time
The reaction rate that is calculated at any specified time while the reaction is proceeding is the
___ - Answer instantaneous rate
Reactant vs time positive slope going up diagonal slope= k. What order type of reaction is this -
Answer second order
Arrange each solution from lowest to highest freezing point assuming each solution has a
volume of 100 mL
1. pure water
2. water with 1 teaspoon of dissolved sugar
3. water with 2 teaspoons of dissolved sugar
4. water with 1/2 teaspoon of dissolved sugar - Answer 3,2,4,1
T/F: a 5.0% NaCl solution has a lower freezing point than a 2.0% NaCl solution - Answer true
, T/F: a 5.0 sucrose solution has a higher boiling point than pure water - Answer true
T/F: a 2.0% NaCl solution has a higher vapor pressure than pure water - Answer false
T/F: A 5.0% sucrose solution has a higher osmotic pressure than a 10% sucrose solution -
Answer false
osmosis - Answer solvent in a less concentrated solution passes through a membrane into a
more concentrated solution
has an inversely proportional relationship with temperature - Answer concentration of the
solution
has a proportional relationship with temperature - Answer osmotic pressure
allows only certain particles to pass through - Answer semipermeable membrane
______ is/are needed to stop the movement of solvent through a membrane - Answer
osmotic pressure
T/F: colligative properties (freezing point depression, boiling point elevation, and osmotic
pressure) have been used to determine the molar mass of a solute - Answer true
When osmotic pressure is kept constant, the relationship between molarity(M) and
temperature (T) is ____ - Answer inversely proportional
T/F: a solution that contains a solvent and non-volatile solute particles has a lower vapor
pressure than a pure solvent under the same conditions - Answer True
what are the 4 colligative properties of a solution - Answer vapor pressure lowering, freezing
point depression, boiling point elevation, and osmotic pressure
The temperature at which the vapor pressure of a liquid is equal to the atmospheric pressure on
