1 / 7

Designing a Hand Warmer

Designing a Hand Warmer. http://group.chem.iastate.edu/Greenbowe/sections/projectfolder/flashfiles/thermochem/solutionSalt.html.

xaria
Télécharger la présentation

Designing a Hand Warmer

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Designing a Hand Warmer

  2. http://group.chem.iastate.edu/Greenbowe/sections/projectfolder/flashfiles/thermochem/solutionSalt.htmlhttp://group.chem.iastate.edu/Greenbowe/sections/projectfolder/flashfiles/thermochem/solutionSalt.html Breaking bonds and particulate attractions absorb E from the surroundings, while forming new bonds and particulate attractions release energy to the surroundings. When an ionic solid dissolves in water, ionic bonds between + and – ions and H bond b/t water molecules are broken, and NEW attractions between water/anions and cations are formed. The E required to break these bonds and form new ones depends on the properties of the anions and cations. Heat evolved, q = -, exothermic Heat absorbed, q = + and endothermic ENTROPY of solution is ALWAYS (+)

  3. Pre-Lab Part A: • Heat Capacity of the Calorimeter Part B: • Practice Calorimetry Procedure with MgSO4(s)

  4. Information in Data Tables

  5. In groups, review the calorimetry procedure and answer the following questions:

  6. Each group will use 3 solids (we will share data at the end) Group A: • ammonium nitrate • Calcium chloride • Sodium acetate Group B: • Sodium chloride • Lithium chloride • Sodium carbonate

  7. Calculations Table

More Related