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Exploring The Effects Of Salt On Freezing Point Depression: A Comparative Study Of Ice Water And Salt Water

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    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. Ho w 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 te mperature 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 β€œreference” 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 calc u lating 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. T he colligative property of freezing point depression is determined by the ratio : π‘π‘’π‘šπ‘π‘’π‘Ÿ π‘œπ‘“ π‘ π‘œπ‘™π‘’π‘‘π‘’ π‘šπ‘œπ‘™π‘’π‘π‘’π‘™π‘’π‘  π‘π‘’π‘šπ‘π‘’π‘Ÿ π‘œπ‘“ π‘ π‘œπ‘™π‘£π‘’π‘›π‘‘ π‘šπ‘œπ‘™π‘’π‘π‘’π‘™π‘’π‘  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 : βˆ† 𝑇 = π‘–πΎπ‘š where βˆ† 𝑇 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 it’s 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

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