Solutions, Acid, and Bases

I. Formation of Solutions A. Dissolving 1. Solute – substance that is dissolved in a solution 2. Solvent – the substance that the solute dissolves in Ex. coffee sugar is the solute and the water is the solvent, Air → N is the solvent b/c it makes up about 78% of air

B. Freezing and Boiling Points 1. Water containing a solute will freeze at a lower temperature and boil at a higher temperature. a. a solute can increase the boiling point and decrease the freezing point Ex. Decreasing freezing point with salt on roads - Adding anti-freeze to radiator decreases freezing point and increases boiling point

II. Properties of Acids and Bases A. Identifying Acids 1. Acid – substance that is able to donate a H+ (hydronium) ion and increases the concentration of when it dissolves in water ex. HCl (hydrochloric Acid), H2SO4 (sulfuric acid) 2. Properties of acids are: a. sour taste - ex. lemons, grapefruits, limes, and oranges b. reactivity with metal

- ex. cover spaghetti sauce with aluminum foil the foil becomes dark and may develop small holes and the sauce will acquire a metallic taste c. produces color changes in indicators - indicator – changes color in presence of an acid or base - Blue litmus paper turns red w/acid

B. Identifying Bases 1. Base – substance that produces (OH-) hydroxide ion when dissolved in water ex. soap properties of bases include: a. bitter taste b. Slippery feel - Soap c. Change in indicator - Change red litmus paper blue

Ex. some flowers can tell you what type of soil they grow in Ex. some flowers can tell you what type of soil they grow in. Hydrangeas are bluish pink they are in acid soil, and pink when in basic soil C. Neutralization – reaction between an acid and base 1. neutralization reaction produces a salt and water Ex. NaOH + HCl → NaCl + H2O (base) (acid) (salt) (water)

II. Stength of Acids and Bases A. The PH Scale – amount of hydrogen ions in a solution (measure with litmus paper) pH 7 = neutral a. amount of H+ ions = OH- ions pH < than 7 = acid a. amount of H+ is > than OH- ions pH > than 7 = base a. amount of H+ is < than OH- ions

B. Limestone is used to balance acidic soil and water. 1. Lakes with limestone bottoms have water with a neutral pH, where as bedrock lakes have acidic water.