Describe the three freezing points. Is there a relationship between the amount of solute in the solution and the freezing temperature? Yes, the more solute the colder the temperature is B. What are some practical applications of freezing point depression? The longer the time, the colder it gets Data Table 4.
Record the temperature. Drop 1 Alka-Seltzer into the beaker. Record the time it takes for the tablet to completely dissolve. Record in data table. Data Table:
Press STOP when the thermograph stabilizes 20. Save that shizzzznit 21. Press DISPLAY to clear previous scan 22. Repeat 11-19 for a second trial | Trial One | Trial Two | Mass of cold water | | | Initial temperature of cold water | | | Mass of hot water | | | Initial temperature of hot water | | | Final Temperature | | | File Name | | | Part B 1. Nest two Styrofoam cups within one another 2.
The purpose of this lab was to find the molecular weight of two unknown substances by analyzing the freezing points in cyclohexane and to provide a visual representation of the freezing point depression effect. The theory of this lab is; by using measurements of mass of the unknown substances (solute) in correlation with the mass of the cyclohexane (solvent) and the freezing point constant of the solvent, you could determine the molecular weight of the solute by using the same math involved in deciding the freezing point of the solution/ The theory behind the visual of the FPD effect is that if one was to record the freezing point of a solution and two solutions of the same substances with more solute, one would see a visible drop in freezing point. The equations you needed for this lab were the freezing point formula for organic substances (ΔFp=(m)Kf) and the
5. Record the data in a chart with the times. Experiment Basically the experiment is on what household items can insulate and hold the circulation of cold air inside the ice box which allows freezing points or melting points to take course. Data/ Graphs Ice Boxes | Test 1(none) | Test 2 (salt) | Test 3(Sugar) | Cardboard | 7:14.8 | 12:52.7 | 8:35.2 | Paper | 9:28.4 | 12:14.8 | 7:43.6 | Aluminum Foil | 16:35.1 | 17:21.6 | 13:17.8 | Time Graph Observations When I experimented I noticed that one of the ice boxes melted quickly than the others, which could mean that those ice boxes vents heat. The substance added to the ice box could have either helped it stay cool or melted it quicker.
Lab: I Scream, We All Scream for …Colligative Properties!? Introduction: When a solute is added to water the physical properties of freezing point and boiling point change. Water normally freezes at 0oC and boils at 100oC. As more solute is added, the freezing point drops (“freezing point depression”) and the boiling point increases (“boiling point elevation”). This property is useful in our lives.
What “magic” did the alchemist Drebble attempt for King Henry? Tried to make a room cold by using a fan, and ice mixed with salt 3. What was the dominant theory about cold in Robert Boyle’s day? Cold was a primordial substance that shrinks when they get cold, and expands as they get warmer 4. What did Boyle’s experiments convince him about cold?
Asking Questions: Asking questions is where we discuss what we are looking for in our scientific practices, asking what, when, where, why, how and who. When asking questions we try to determine things like, what are we trying to accomplish? Why are we carrying out this scientific inquiry? How are we going to proceed? Who, the history of important people related to the scientific inquiry.
Using another 125-mL flask, 60-mL of 0.3622 M potassium hydroxide in ethanol was deposited. Both flasks were clamped in a temperature-controlled bath regulated at 50.0˚C. The solutions were then set in the temperature bath for ten minutes to equilibrate. An empty 250-mL Erlenmeyer flask was also clamped in the same water bath. In another flask 50-mL of ice water was deposited with three-drop phenolphthalein.
The absorption spectrum is measured using a spectrophotometer and the data is graphed in Excel. The peak of the line is used to find Vmax of Fe2+. Vmax is used to find the moles of Fe2+ and ligand. The unknown n is a ratio of moles ligand divided by moles Fe2+. Results and Discussion For the first part of the experiment (Part A), five different 100 mL volumetric flasks were each filled with 1,2,3,4 and 5 mL of iron (II) solution.