Instructions: 1. fill the beaker with crushed ice. suspend a thermometer in the ice so the bulb of the thermometer is close to but does not touch the bottom of the beaker. 2. record the temperature of the contents in the beaker. 3. warm the beaker with the heat source. stir gently. be careful not to let the thermometer touch the beaker. 4. record the temperature every fifteen seconds. note the states in the beaker on a separate sheet of paper each time the temperature is recorded. 5. record several temperatures at intervals as the water begins to boil. compile a summary of your findings during this investigation. be sure to answer the questions below and include your hypothesis, observations, data, interpretation, and conclusion in your report. what was the temperature of the ice before you added heat? what was the temperature as the ice melted? at what temperature did the water begin to boil? did the temperature of the water rise or remain constant as the water boiled? if the temperature did not change while heat was being added, what was happening to the ice or the water at that time? what do you think the heat was used for if not to raise the temperature? was there room for human error in your investigation? why or why not? what did you learn from this investigation? be thoughtful in your answer.

the missing options are :

(1) lower boiling point and a lower freezing point(2) lower boiling point and a higher freezing point(3) higher boiling point and a lower freezing point(4) higher boiling point and a higher freezing point

answer : the correct answer is option (3) higher boiling point and a lower freezing point

explanation :

when a non volatile solute is added to a solvent like water, it results in elevation of boiling point.

let us find the increase in boiling point of water when cacl₂ is added to water to make a solution of 1 m

step 1 : find molality of the solution

let us assume we have 1 l of solution.

let us convert this to grams of cacl₂.

molar mass of cacl2 is 111 g/mol

grams of cacl₂ =

mass of solute = 111 g

assuming density of solution same as water which is 1g/ml we have ,

mass of solution = density * volume

mass of solution =

mass of solution = mass of solvent + mass of solute

mass of solute = 1000g - 111g

mass of solute 889 g = 0.889 kg

the molality of the solution can be calculated as

molality = 1.12 m

step 2 : find boiling point elevation.

the elevation in boiling point is calculated as

here δtb = boiling point elevation

i = vant hoff factor which is the number of ions formed by the solute .

cacl₂ dissociates as

it forms 3 ions . therefore,

i = 3

m = molality which is 1.12 m

kb is constant for a given solvent. for water it is 0.512

the boiling point of water increases by 1.7 °c

step 3: find freezing point depression.

when a non volatile solute is added to water, it results in decrease in freezing point.

the formula to find freezing point depression is

kf is constant for water and its value is 1.86

the freezing point of water decreases by 6.2 °c

therefore we can say that, the solution will have a higher boiling point and a lower freezing point