Solution Properties and Effects on Temperature, Pressure, and Concentration

1. Solutions

2. A solution is a mixture that has no visible boundaries among its components (i.e. a homogeneous mixture) Vinegar: water + acetic acid (+ others) Brass: copper + zinc Silberberg, M. 2010. Principles of General Chemistry. 2nd ed. New York: McGraw-Hill. http://www.thekitchn.com/thekitchn/good-questions/what-can-i-do-with-datu-puti-filipino-coconut-vinegar-good-questions--119557http://www.ehow.com/about_6369891_brass-alloy-information.html

3. The components of a solution may either be solid, liquid, or gas Brown, , E. LeMay, and B. Bursten. 2000. Chemistry: The Central Science. 8th ed. Phils: Pearson Education Asia Pte. Ltd. Chang, R. 2002. Chemistry 7th ed. Singapore: McGraw-Hill.

4. A solution contains a solvent and solute(s):The solvent is present in larger amount, while the solute(s) is/are present in smaller amount/s Chang, R. 2002. Chemistry 7th ed. Singapore: McGraw-Hill.

5. A molecular view of the solution process

6. When salt is placed in a glass of water,it dissolves http://img.webmd.com/dtmcms/live/webmd/consumer_assets/site_images/articles/health_tools/sore_throat_slideshow/photolibrary_photo_of_salt_sprinkled_into_water.jpg

7. When the solute dissolves in the solvent, particles of the solute disperse throughout the solvent solvent-solvent interaction solute-solute interaction solvent-solute interaction remember your IMFAs! Chang, R. 2002. Chemistry 7th ed. Singapore: McGraw-Hill.

8. > solvent-solvent attraction solution process unfavorable solute-solvent attraction & < solute-solute attraction solution process favorable To determine if a solution will form, the three types of interaction are considered Chang, R. 2002. Chemistry 7th ed. Singapore: McGraw-Hill.

9. Effect of temperature on solubility (water solvent, gas solute)

10. Solubility is the amount of solute that dissolves in a fixed amount of solvent at a given temperature i.e. solubility of NaCl at 100°C = 39.12 g/100 mL H2O 20.00 g NaCl + 100 mL H2O 39.12 g NaCl + 100 mL H2O 40.00 g NaCl + 100 mL H2O Chang, R. 2002. Chemistry 7th ed. Singapore: McGraw-Hill.

11. Gas solubility in water decreases with increasing temperature • There are relatively weak IMFAs between gas and water • When temperature rises, the gas molecules get enough energy to overcome the weak IMFAs • The gas molecules leave the solution Silberberg, M. 2010. Principles of General Chemistry. 2nd ed. New York: McGraw-Hill.

12. During many industrial processes, large amounts of water are taken from a nearby river or lake, pumped through the system to cool materials, and then returned to the water body at a higher temperature Silberberg, M. 2010. Principles of General Chemistry. 2nd ed. New York: McGraw-Hill. http://www.earthscienceworld.org/images/search/results.html?Keyword=Thermal%20Pollution#null

13. The reduced solubility of O2 gas in hot water has a direct bearing on thermal pollution, which is the heating of waterways to temperatures that are harmful to its living inhabitants • increase in water temperature accelerates fish’s metabolism • fish’s need for oxygen increases • supply of oxygen decreases Chang, R. 2002. Chemistry 7th ed. Singapore: McGraw-Hill. http://www.dec.ny.gov/animals/32847.html

14. Effect of pressure on solubility (water solvent, gas solute)

15. Gas solubility in water increases with increasing pressure P1 at equilibrium P2 is applied P2 at equilibrium Silberberg, M. 2010. Principles of General Chemistry. 2nd ed. New York: McGraw-Hill.

16. Gas solubility in water increases with increasing pressure • At a given pressure, the same number of gas molecules enter and leave the solution (that is, the system is at equilibrium) • If the pressure increases, gas particles collide with the liquid surface more often • More gas particles enter than leave the solution per unit time, thereby increasing the solubility of the gas Silberberg, M. 2010. Principles of General Chemistry. 2nd ed. New York: McGraw-Hill.

17. The effect of pressure on solubility is seen when one opens a bottle of a carbonated beverage (champagne, beer, or soft drinks) • carbonated beverage is bottled under a CO2 pressure greater than atmospheric pressure • when the bottle is opened, CO2 pressure above the solution is decreases • CO2 solubility decreases • CO2 bubbles out of solution Brown, , E. LeMay, and B. Bursten. 2000. Chemistry: The Central Science. 8th ed. Phils: Pearson Education Asia Pte. Ltd. Chang, R. 2002. Chemistry 7th ed. Singapore: McGraw-Hill.

18. Expressing Concentration Concentration is the amount of solute in a given amount of solution. - Percent (% w/w, %v/v) - parts per million (ppm), parts per billion (ppb), parts per trillion (ppt) - Molarity (moles/L)

19. A typical aspirin tablet contains 300. mg of the active ingredient, acetylsalicylic acid. What is the average concentration, expressed as percentage by weight (% w/w), of acetylsalicylic acid in the body of a 165-pound person who has just taken two aspirin tablets. • Iodized salt may be prepared by mixing in a small amount of potassium iodide in table salt (7.6 x 10-5 g of KI per gram of table salt). What is the concentration of KI in iodized salt expressed in ppm?

20. The maximum permitted level of mercury in drinking water is 0.002 ppm. Analysis of 250.-mL sample of tap water was found to contain 0.550 moles of Hg. Is this water supply safe for consumption? • The Safe Drinking Water Act of 1974 (US) sets a maximum of 160. mg of sodium per liter of drinking water. What is the maximum molarity of sodium chloride permitted in community drinking water?