1. a. They are good electrical conductors. The white solids form colorless solutions. b. They are the same compound. Colors are the same.
2. The sugar does not dissociate into ions.
Solid state: hydrogen bonding in hydroxyl groups Dissolved state: hydrogen bonds are between the water molecules and the sugar molecule.
Solid state: www.chm.bris.ac.uk
Dissolved state: http://beyondpenguins.ehe.osu.edu/teaching-about-snowflakes-a-flurry-of-ideas-for-science-and-math-integration
The dissolving of sucrose is a physical change.
Solid state: Dissolved state:
Solid state: http://www.chemistry.wustl.edu/~coursedev/Online%20tutorials/Solutions.htm Dissolved state: http://www.elmhurst.edu/~chm/vchembook/171solublesalts.html
Ionic attractions are overcome. This is a ambiguous change.
4. Yes, since both changes were physical, the compound is not changed.
5. The sucrose molecule does not dissociate into ions so the water molecules are surrounding the whole molecule. Sodium chloride dissolves in an aqueous solution so the water molecules are surrounding the individual ions, Na+ and Cl-. This explains the conductivity of sodium chloride in B.3.a. The ions of sodium chloride dissociate in solution and the freely moving ions conduct electricity. In sucrose, the molecule doesn’t dissociate into ions and therefore does not conduct electricity.
6. Ambiguous change. The ionic attractions are being overcome in the NaCl; however, the compound has not changed.
7. a. Co (H2O) 62+ the solution was more pink and then blue. b. dipole forces.
http://www.chemthes.com/entity_datapage.php?id=3985 c. The CoCl42- because the solution was blue violet. d. polar O-H bonds attracted to the ion.