disolving sucrose, NaCl< and calcium chloried affect the boiling point of frezing point of water. Assuming that you have 0.1m solution of all these 3 compounds:
a)rank then in order of decreasing freezing point.
b) rank in order of increasing boiling point
c)why do the affected the boiling point and freezing point of water differently?
You should read the posts to see what they say. Yours doesn't make sense but I can guess at what you omitted.
delta T = i*Kf*molality
delta T = i*Kb*molality.
Since molality is the same for all three solution, that is not a factor. Kf or Kb is the same for all three solutions, also; therefore, that is not a factor.
i is the number of particles. Sucrose has 1, NaCl has 2, CaCl2 has 3. That's the difference. Now you can answer 1 and 2.
Thank you Drbo22...but if it dosent make sence I'm sorry but that's what the tearche wrote in the paper he gave us...
If the instructor started the sentence with a small letter instead of a capital letter, wrote < instead of a , after NaCl, and misspelled or (of), then shame on him/her. My guess is those are typos in transferring the problem to this board. It would have made all the difference in the world, as I read the post, if you had written Dissolving sucrose, NaCl, or CaCl2 .....
Even if the instructor wrote it incorrectly, it would have helped if you had corrected it to make your question a little easier to understand. Thanks for using Jiskha and do come back.
To rank the compounds in order of decreasing freezing point and increasing boiling point, we need to consider their ability to lower or raise the freezing and boiling points of water.
a) Ranking in order of decreasing freezing point:
When dissolved in water, all three compounds - sucrose, NaCl, and calcium chloride - will affect the freezing point. However, we need to consider the number of ions each compound produces when it dissolves.
Sucrose does not dissociate into ions when dissolved, so it only adds solute particles without increasing the number of ions in solution. Therefore, it will have the least effect on the freezing point of water.
NaCl dissociates completely into two ions (Na+ and Cl-) when dissolved, which increases the number of solute particles in solution. Calcium chloride (CaCl2) dissociates into three ions (Ca2+ and 2 Cl-) when dissolved, resulting in even more solute particles.
So, the ranking in order of decreasing freezing point will be:
Calcium chloride > NaCl > Sucrose
b) Ranking in order of increasing boiling point:
Both the elevation of boiling point and depression of freezing point are affected by the number of solute particles in solution. Hence, the ranking for increasing boiling point will be the same as for decreasing freezing point:
Sucrose < NaCl < Calcium chloride
c) Difference in effect on boiling and freezing points:
The difference lies in the mechanism by which solute particles affect the boiling and freezing points of water. In both cases, solute particles disrupt the formation of the solid crystal lattice or the vapor phase.
For the freezing point, solute particles interrupt the formation of the crystal lattice structure by occupying space between water molecules. This makes it more difficult for the water molecules to arrange into a solid structure, resulting in the depression of the freezing point.
On the other hand, for the boiling point, the presence of solute particles restricts the ability of water molecules to escape into the vapor phase. The particles essentially increase the number of collisions between water molecules, requiring more energy to overcome these interactions and reach the boiling point. Therefore, the boiling point is elevated.
The extent of the freezing point depression and boiling point elevation depends on the concentration and nature of the solute particles present in the solution.