Exploring The Effects Of Salt On Freezing Point Depression: A Comparative Study Of Ice Water And Salt Water
This Homework Answers document investigates the impact of salt on freezing. Download now!
Chloe Harris
Contributor
4.5
57
2 days ago
Preview (2 of 2)
Sign in to access the full document!
Exploring the Effects of Salt on Freezing Point Depression: A Comparative
Study of Ice Water and Salt Water
1. compare your readings taken for the ice water and salt water. How do you explain the observed
temp change?
By considering the readings taken for ice water and salt ice water we can observe a lower
temperature in the case of the salt water beaker. Indeed if salt is added to water it lowers the
temperature of change phase (from liquid to solid and from solid to liquid). In order to change phase
from solid to liquid, heat energy is required from the surrounding environment so as to snap
hydrogen bonds that hold ice together : due to the salt added the freezing point is lowered therefore
more energy is required to melt the ice. In the salt solution some ice melts and some of the salt is
dissolved : heat is drawn from the ice that makes it colder : ice keeps melting to reach the freezing
temperature point of the salt solution.
2. explain why salt was added to only one of the beakers
Salt was added to only one of the beaker so as to compare the temperature of both beaker and to
analyze the effects of salt on the freezing point of the solution : the beaker without salt can be
considered as a βreferenceβ solution from which all the measures of the salt water beaker will be
compared.
3. salt is a strong electrolyte that produces two ions, Na+ and cl- when it dissociates in water. explain
why this is important to consider when calculating the colligative property of freezing point
depression
A freezing-point depression occurs when a solute (salt) is added to a solvent (water) and produces a
decrease in the freezing point. The colligative property of freezing point depression is determined by
the ratio : ππ’ππππ ππ π πππ’π‘π ππππππ’πππ
ππ’ππππ ππ π πππ£πππ‘ ππππππ’πππ In the case of salt water the number of dissolved particles is
greater than ice water because of the presence of salt dissolved in the water. Two ions are produced
when salt dissociates in water (Na+ and Cl-) : the presence of a solute lowers the freezing point of a
pure solvent solution (ice water considered as a pure solvent), the decrease in temperature is
proportional to the number of dissolved particles in the solution. A useful formula to estimate the
change in freezing point is : βπ = ππΎπ where βπ is the change in freezing point temperature, i is the
number of ions present per formula unit (in this case i = 2) and K is the freezing point depression
depression constant for the solvent (K = 1.86Β°C.kg/mol for water)
4. predict wheather it would be better to use coarse rock salt or fine table salt when making
homemade ice cream. Explain?
In order to make ice cream itβs better to use the coarse salt. But in order to produce rapid cold table
salt would be better. Indeed if you use table salt the salinity of the melting water increases to
Study of Ice Water and Salt Water
1. compare your readings taken for the ice water and salt water. How do you explain the observed
temp change?
By considering the readings taken for ice water and salt ice water we can observe a lower
temperature in the case of the salt water beaker. Indeed if salt is added to water it lowers the
temperature of change phase (from liquid to solid and from solid to liquid). In order to change phase
from solid to liquid, heat energy is required from the surrounding environment so as to snap
hydrogen bonds that hold ice together : due to the salt added the freezing point is lowered therefore
more energy is required to melt the ice. In the salt solution some ice melts and some of the salt is
dissolved : heat is drawn from the ice that makes it colder : ice keeps melting to reach the freezing
temperature point of the salt solution.
2. explain why salt was added to only one of the beakers
Salt was added to only one of the beaker so as to compare the temperature of both beaker and to
analyze the effects of salt on the freezing point of the solution : the beaker without salt can be
considered as a βreferenceβ solution from which all the measures of the salt water beaker will be
compared.
3. salt is a strong electrolyte that produces two ions, Na+ and cl- when it dissociates in water. explain
why this is important to consider when calculating the colligative property of freezing point
depression
A freezing-point depression occurs when a solute (salt) is added to a solvent (water) and produces a
decrease in the freezing point. The colligative property of freezing point depression is determined by
the ratio : ππ’ππππ ππ π πππ’π‘π ππππππ’πππ
ππ’ππππ ππ π πππ£πππ‘ ππππππ’πππ In the case of salt water the number of dissolved particles is
greater than ice water because of the presence of salt dissolved in the water. Two ions are produced
when salt dissociates in water (Na+ and Cl-) : the presence of a solute lowers the freezing point of a
pure solvent solution (ice water considered as a pure solvent), the decrease in temperature is
proportional to the number of dissolved particles in the solution. A useful formula to estimate the
change in freezing point is : βπ = ππΎπ where βπ is the change in freezing point temperature, i is the
number of ions present per formula unit (in this case i = 2) and K is the freezing point depression
depression constant for the solvent (K = 1.86Β°C.kg/mol for water)
4. predict wheather it would be better to use coarse rock salt or fine table salt when making
homemade ice cream. Explain?
In order to make ice cream itβs better to use the coarse salt. But in order to produce rapid cold table
salt would be better. Indeed if you use table salt the salinity of the melting water increases to
Preview Mode
Sign in to access the full document!
100%
Study Now!
XY-Copilot AI
Unlimited Access
Secure Payment
Instant Access
24/7 Support
Document Chat
Document Details
Subject
Chemistry