Question 1
What amount of oxygen is needed to completely react with one mole of CH4?
2 molecules
2 moles
2 atoms
2 grams
Question 2
All of the following are variables in the freezing point equation EXCEPT
Temperature
Change in Temperature
Cryoscopic constant
Van’t Hoff factor
Question 3
1.86 C kg/mol
Question 4
When the limiting reactant in a chemical reaction is completely used the
Excess reactants begin combining
The reaction slows down
The reaction stops
The reaction speeds up
Question 5
Which of the following are colligative properties?
Freezing point
Boiling point elevation
Vapor pressure lowering
All of the options are colligative properties
Question 6
Calculate the molecular weight for the reactants CuSO4 and NaOH.
CuSO4 = 127.55 g/mol and NaOH = 22.99 g/mol
CuSO4 = 143.62 g/mol and NaOH = 38.99 g/mol
CuSO4 = 223.17 g/mol and NaOH = 40.00 g/mol
CuSO4 = 159.61 g/mol and NaOH = 39.99 g/mol
Question 7
Hydrogen and nitrogen react to form ammonia according to the reaction:
3H2 + N2 2NH3
If 4.0 moles of H2 and 2.0 moles of N2 are reacted, how would you know if this is a limiting
reaction problem?
Mass of two reactants are given
Mass is conserved in the problem
Moles are not conserved in the problem
None of the above
Question 8
The cryoscopic constant depends on the properties of the
Solute
Solvent
Solution
Moles
Question 9
Which solution of salt (NaCl or CaCl2) is better to salt the roads? Use the data in the
Determining Molar Mass from Freezing Point experiment to explain your reasoning?
Based on my experimental data, NaCl would be the better choice for salting roads. My data reflected that
freezing point depression was greater with NaCl than CaCl2
Question 10
Freezing point depression occurs when
The freezing point of a given liquid is crystallized
The freezing point of a given liquid is lowered when another compound is added to the
solvent
The freezing point of a given liquid is raised when another molecule is added to the solution
The freezing point of any liquid becomes crystallized
Question 11
Osmoles are the number of solutes in a solution that contributes toward osmotic pressure. We can factor
osmoles into the number of moles of the given substance, which when divided by mass, gives the
molecular mass.
Question 12
The freezing point refers to the point at which a liquid transitions to a solid. This is also known
as the
Melting point
Crystallization point
Dipole dipole moment
Polar breaking moment
Question 13
How many moles of sodium hydroxide are needed to balance the reaction CuSO4 + __ NaOH
Cu(OH)2 + Na2SO4,?
1
2
3
4
Question 14
Review the procedure you completed in the Determining Molar Mass from Freezing Point lab.
Describe any deviations from the experimental procedures, which may have contributed to the
molar masses being different than the theoretical.
I personally had issues with my solution becoming supercooled, which made it difficult to record accurate
freezing points.
In addition, inaccurate mass measurements for the solution could have contributed to incorrectly
calculated molar masses.
Question 15
What are colligative properties? Give the definition and examples of a few.
Colligative properties are properties of a solution that depends on the ratio of solute-to-solvent, but not the
type of solute. Such properties include the changes in vapor and osmotic pressure, changes in freezing
point due to depression, and changes in boiling point.