1. Solutions, Acids, Bases & pH

2. Solute –substance whose particles are dissolved in a solution
ie. salt, sugar
Solvent – the substance in which the solute dissolves
ie. water “universal solvent”

4. Dispersion of Sugar in Water

5. Properties of Liquid Substances
Conductivity – ability to conduct electricity
Freezing point – decreases
Boiling point – increases
Heat of solution – energy is absorbed or released during the formation of a solution
Energy released = exothermic
Energy absorbed = endothermic

6. Factors Affecting Dissolving Rate
Surface area – ↑ surface area = ↑ rate
Stirring – moves dissolved particles away from the solid
Temperature – ↑ temperature = ↑ rate

7. Factors Affecting Dissolving Rate

8. One of the most important aspects of a living system is the degree of acidity or alkalinity

9. Ionization of water -breaking apart water molecules into ions of opposite charge
HOH + HOH  H3O+ + OH-
(water) (water) (hydronium) (hydroxide)

10. Acid – ionic compound that produces hydronium ions (H3O+) when dissolved in water
Stronger acid = more hydronium ions
Number of hydronium ions in solution is greater than the number of hydroxide ions

11. Acids Characteristics of Acids Examples of Acids Tastes sour
Reacts strongly with metals
Conducts electricity in water
Turns blue litmus paper red
Generally clear solutions
Proton donors (give H+)
Examples of Acids
Vinegar H2SO4
Citrus fruits HNO3
Stomach acid (HCl)

12. Acetic acid CH3COOH Vinegar
Carbonic acid H2CO3 Carbonated beverages
Hydrochloric acid HCI Digestive juices in stomach
Nitric acid HNO3 Fertilizer production
Phosphoric acid H3PO4 Fertilizer production
Sulfuric acid H2SO4 Car batteries

13. Add Base to Water
OH-
Na+
Base – ionic compound that produces hydroxide ions (OH-) when dissolved in water
NaOH  Na+ + OH-
Stronger base = more hydroxide ions
Number of hydroxide ions in solution is greater than the number of hydronium ions

14. Bases Characteristics of Bases Examples of Bases Tastes bitter
Reacts strongly with metals
Conducts electricity in water
Turns red litmus paper blue
Generally slippery feel
Proton acceptors (take H+)
Examples of Bases
Lye (NaOH) Ca(OH)2
Ammonia (NH3) KOH

15. Aluminum hydroxide Al(OH)3 Deodorant, antacid
Calcium hydroxide Ca(OH)2 Concrete, plaster
Magnesium hydroxide Mg(OH)2 Antacid, laxative
Sodium hydroxide NaOH Drain cleaner, soap production

16. Neutralization Reaction between an Acid & Base that forms salt & water
HCl NaOH  HOH + NaCl
(Hydrochloric Acid) + (Sodium Hydroxide)  (Water) (Salt)

17. Sodium chloride NaCl Food flavoring, preservative
Sodium carbonate Na2CO3 Used to make glass
Potassium chloride KCl Used as a salt substitute to reduce dietary intake of sodium
Potassium iodide Kl Added to table salt to prevent iodine deficiency
Magnesium chloride MgCl2 De-icer for roads
Calcium carbonate CaCO3 Chalk, marble floors, and tables
Ammonium nitrate NH4NO3 Fertilizer, cold packs

18. Remember!! During a chemical reaction: Bonds are broken
Elements are rearranged
New compounds are formed
Balanced Equation - # of atoms of each element are equal on both sides of a chemical equation
Reactants are shown on the left
Products are shown on the right
HCl + NaOH  H2O + NaCl
Reactants Products

19. pH Scale Measure of hydronium (H3O+) ion concentration
pH affects the physical & chemical properties of a substance

20. Acid – pH = 0-6
Neutral – pH = 7
Base – pH = 8-14

21. A change of 1 pH unit changes the H3O+ concentration by a factor of 10
A change of one pH unit changes the H+ concentration by a factor of 10.
A change of 1 pH unit changes the H3O+ concentration by a factor of 10
ie. pH 1 has 10x more hydronium ions than pH 2; 100x more than pH 3, etc.

22. Why do we need to know pH?

23. Indicator Changes color as the pH changes
Indicates the pH of the solution

24. Works Cited www.chem4kids.com www.pasco.com faculty.fmcc.suny.edu
creekconnections.allegheny.edu
Physical Science Concepts In Action Textbook