week 4 post lab - Week 4 Freezing Point Depression Question...

Info icon This preview shows pages 1–2. Sign up to view the full content.

Week 4: Freezing Point Depression Question: How can you use the colligative property of freezing-point depression to experimentally determine the freezing constant of a solvent? Experimentally determine the K f of stearic acid. Compare literature value with percent error. Results Section: The question was to find the K f of stearic acid which was 2.0. This greatly differs from the theoretical result of 4.5. The experimental method we have used is we first combined of3.001 grams Lauric acid with 6.036 grams of stearic acid to explore colligative properties and obtain a freezing point. We then again took 6.036 (carefully measured again) grams of stearic acid and found it’s freezing point. The molality of the solution was then found and so was the difference in temperature. We plugged this into the equation to find the KF. Table 1. The Data and the Result (K f of stearic acid) Room Temperature of Solution 19.7 °C Grams of Stearic acid used 3.001g Grams of Lauric acid used 6.036 g Freezing Point of Stearic Acid 66 °C Freezing Point of solution (Lauric acid and Stearic acid) 57 °C Difference of the two temperatures (DT f ) 9 °C i ( van’t hoff factor): 1 M (molal concentration) 2.49 (mol/kg) K f: 3.6 Theoretical Yield 4.5 Percent Error 20 % Table 1. This table shows the data and the results of this lab. The actual result (which was to find the K f ) is underlined while the rest are data along with the percent error. The data includes the
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

Image of page 2
This is the end of the preview. Sign up to access the rest of the document.
  • Spring '07
  • WINGRAVE
  • Chemistry, Colligative properties, Freezing-point depression, stearic acid, 3.001g

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern