Solutions: More Vocab

1. Solutions:More Vocab

2. Soluble soluble: capable of being dissolved asubstance that dissolves in another substance is said to besolublein that substance Insoluble a substance that does not dissolve in another substance

3. solubility:maximum amount substance that dissolves in given amount of another substance • LIMITEDamount solute that dissolves in given amount solvent • affected by temperatureandpressure

4. rate of dissolving is different from amount that will dissolve! • rate is how fast • amount is how much

5. factors that affect the rate of dissolving: • temperature • stirring or agitation • amount of surface area of solute • amount of solute already dissolved

6. source dissolving is physical change dissolve covalent substances: produce MOLECULES in solution C6H12O6(s) + H2O(l)C6H12O6(aq)

7. dissolve ionic substances: produce IONS in solution NaCl(s)+H2O(l) Na+1(aq) + Cl-1(aq)

8. Solvation • interaction between solvent & solute particles • solute particles surrounded by solvent particles during dissolving process • SOLUTE particles may be: • ions • polar molecules • non-polar molecules • SOLVENT molecules may be: • polar • non-polar

9. Solvation in different systems.

10. Hydration describes solvent-solute interaction when solvent is water

11. dissolving ionic compounds: molecule-ion interaction solute-solvent interaction must be greater than: interaction between solute particles for dissolving to occur

12. Solubility • amount solute dissolved in specific amount solvent at givenTEMPERATURE and PRESSURE • units: grams solute per 100 grams solvent

13. Solubility Curves of Selected SOLIDS Table G solubility traces for mostsolids have (+) slopes; hotter the solvent, the more solute can dissolve

14. Solubility Curves of Selected GASES solubility traces for all gases have (–) slopes Do you know why most fish prefer cold water?

15. Vocabulary Interlude • miscible two liquids that WILL MIX together: water and ethanol are miscible in all proportions • immiscible two liquids that will NOT MIX together: oil and water are immiscible

16. Oil & H2O are immiscible

17. Matter Mixtures Pure Substances Homogeneous Mixtures = Solutions Elements Compounds Heterogeneous Mixtures Conduct current Nonconductor Types of Solutions

18. What do you need to conduct electricity? mobile, positively charged particles!!!!

19. Vocabulary Interlude • electrolyte: • substancethat dissolves in water to form solution that conducts electricity • charged ions present in solution • non-electrolyte: • substance that dissolves in water to form solution that does NOT conduct electricity • neutral moleculespresent in solution

20. electrolyte vs. non-electrolyte Which solution conducts a current?

21. Dilute vs. Concentrated • concentrated • large amounts of solute present • dilute • small amounts of solute present

22. Which solution is most dilute? most concentrated? How can you tell? thestrongerthecolor, themore concentratedthe solution

23. to dilute a solution: add MORE solvent

24. the # is the same! Which solution is more concentrated? More dilute? What can you say about the #of solute particlesin pictures A and C? A C A B C

25. solubility amount solute required to form saturated solution

26. unsaturated solution LESSthan maximum amountsolutethat willdissolveat given T and P

27. saturated solution • maximum amount of solute has been dissolved at given T & P • no more solute will dissolve

28. The solution is saturated when the solute stops dissolving 

29. Dynamic Equilibrium in Saturated Solution microscopic level: rate dissolving = rate recrystallization macroscopic level:no apparent change

30. Supersaturated Solution • containsmoresolute than saturated solution • VERY unstable • very tricky to make these • need to use heat

31. testing for saturation: add additionalcrystalsof soluteinto solutionand see what happens

32. unsaturated solution crystals dissolve:

33. saturated solution • crystals sink to bottom of solution:

34. supersaturated solution Bam! suddenly have lots of solid solute in beaker:

35. How do terms saturated, unsaturated & supersaturated fit in with the solubility curves?

36. saturatedsolns: • any point ontrace line (max solute dissolved) supersaturatedsolns: • all points above trace lines(more than max) unsaturated solutions: • all points below trace lines (less than max)

37. characterize points A, B, C, D with respect to KNO3 trace line (dilute, concentrated, saturated, unsaturated, or supersaturated) A B C D D = dilute & unsaturated A,C = concentrated & supersaturated B=concentrated & saturated

38. Solubility Graphs • traces: have positive or negative slopes • most solids have positive slope • the hotter the water, the more solute dissolves • The colder the water, the less solute dissolves • all gases have negative slope • the hotter the water, the less gas dissolves • The colder the water, the more gas dissolves

39. Summary of Dissolving • occurs at surface of solid • interaction: betweensolute &solvent • interaction called “solvation” • interaction called “hydration” (if solvent is H2O) • involves: change in energy