溶解度导学案设计（Solubility guiding case design）.docVIP

溶解度导学案设计（Solubility guiding case design） Tian Zhen Central School in 2011 last semester, grade nine chemistry instruction study case taught time: day and month Study Unit ninth: solution subject two: solubility (first class) guided learning case design: asking for learning Process 7, method guidance: determine whether the solution is saturated At a certain temperature, the presence of residual solute dissolved in the solution can not continue to observe, if there is no longer reduces and the solute, solute and solution coexist, then this solution is the solute saturated solution; if there is no residual solute, may be the solute unsaturated solution, may also be a saturated solution of the solute the. 8. Knowledge extension: think again why the solid will increase after the cooling of the potassium nitrate solution And the soup left in the pot, if its heating all the time, why does the bottom of the pot appear white? 9, explain the principle of crystallization: the cooling of hot solution or the decrease of the amount of solvent, the solute that has dissolved in the solution is precipitated in the form of crystal in solution, and this process is called crystallization. What solution do you think must be the solution that has been crystallized? Does the crystal belong to the solute in the solution? (knowledge reproduction: dissolved substance called solute) 10. According to this, can you generalize the solution crystallization method? And please combine your understanding of the process and principle of P35 sea salt drying. Three, class test: A 1. potassium nitrate solution at 20 DEG C, not to dissolve the potassium nitrate solution as the solution, the solution temperature rises to 100 degrees, 100 degrees the potassium nitrate solution is the solution. (fill in saturation or unsaturated) 2. at a certain temperature to add enough of the solute a solution, after adding the solute mass oscillation does not reduce, the original solution is a solution; then the mixture