CHEM 162 EXPERIMENT 2 ELECTROCHEMISTRY
FINAL PAPER 2026 TESTED QUESTIONS WITH
FULL SOLUTION GRADED A+
◉ What colligative property is displayed by making ice cream?
Answer: freezing point depression
◉ Why is salt added to ice when trying to facilitate freezing point
depression? Answer: because the solution freezes at a lower
temperature than water
◉ T/F: Colligative properties depend only on the number and not
the identity of the solute particles in a solution. Answer: True
◉ freezing point Answer: the temp at which the solvent in solution
and the pure solid solvent have the same vapor pressure (basically,
solid and liquid are coexisting)
◉ What causes freezing point depression (why are lower temps
needed to freeze something)? Answer: solute particles interfere
("stand between") the solvent particles, weakening the
intermolecular forces and therefore lowering the freezing point
,◉ molality equation Answer: m = moles solute / kg solvent
◉ solute Answer: material dissolved in something
◉ solvent Answer: material dissolving something
◉ freezing point depression equation Answer: ∆t_f = t_f solution - t_f
solvent
◉ K_f value for water Answer: -1.86 ºC/m
◉ equation relating freezing point and van't Hoff factor Answer: ∆t_f
= iK_fm
◉ In the freezing point depression experiment, what temperature is
the ice/salt bath supposed to be at? Answer: -10 ºC
◉ In the freezing point depression experiment, what was the solute?
Solvent? Answer: solute: isopropyl alcohol
solvent: water
◉ percent error equation Answer: | (experimental - theoretical)/
theoretical | x 100%
, ◉ difference b/t molarity and molality Answer: molarity: mols
solute/ L solution
molality: mols solute/ kg solvent
◉ As van't Hoff factor increases, does freezing point increase or
decrease? Answer: decrease
◉ If the calculated molar mass of a compound is 10, but the actual
molar mass is 5, what should the van't Hoff factor be? Answer: 1/2
◉ What does the green dye react with that causes its color to
change? What color does it change to? Is this the result of a
structural change? Answer: - a Lewis base
- colorless
- yes
◉ aromatic compound Answer: contains plantar ring systems with
alternating double bonds; ex: dyes
◉ chromophore Answer: the part of the molecule responsible for its
color
FINAL PAPER 2026 TESTED QUESTIONS WITH
FULL SOLUTION GRADED A+
◉ What colligative property is displayed by making ice cream?
Answer: freezing point depression
◉ Why is salt added to ice when trying to facilitate freezing point
depression? Answer: because the solution freezes at a lower
temperature than water
◉ T/F: Colligative properties depend only on the number and not
the identity of the solute particles in a solution. Answer: True
◉ freezing point Answer: the temp at which the solvent in solution
and the pure solid solvent have the same vapor pressure (basically,
solid and liquid are coexisting)
◉ What causes freezing point depression (why are lower temps
needed to freeze something)? Answer: solute particles interfere
("stand between") the solvent particles, weakening the
intermolecular forces and therefore lowering the freezing point
,◉ molality equation Answer: m = moles solute / kg solvent
◉ solute Answer: material dissolved in something
◉ solvent Answer: material dissolving something
◉ freezing point depression equation Answer: ∆t_f = t_f solution - t_f
solvent
◉ K_f value for water Answer: -1.86 ºC/m
◉ equation relating freezing point and van't Hoff factor Answer: ∆t_f
= iK_fm
◉ In the freezing point depression experiment, what temperature is
the ice/salt bath supposed to be at? Answer: -10 ºC
◉ In the freezing point depression experiment, what was the solute?
Solvent? Answer: solute: isopropyl alcohol
solvent: water
◉ percent error equation Answer: | (experimental - theoretical)/
theoretical | x 100%
, ◉ difference b/t molarity and molality Answer: molarity: mols
solute/ L solution
molality: mols solute/ kg solvent
◉ As van't Hoff factor increases, does freezing point increase or
decrease? Answer: decrease
◉ If the calculated molar mass of a compound is 10, but the actual
molar mass is 5, what should the van't Hoff factor be? Answer: 1/2
◉ What does the green dye react with that causes its color to
change? What color does it change to? Is this the result of a
structural change? Answer: - a Lewis base
- colorless
- yes
◉ aromatic compound Answer: contains plantar ring systems with
alternating double bonds; ex: dyes
◉ chromophore Answer: the part of the molecule responsible for its
color
