Do Now What is pH? Do you have the same pH everywhere in your body?

ACIDS & BASES Acids: always (almost) begin with "H" because of the excess of H+ ions (hydrogen)Acids: always (almost) begin with "H" because of the excess of H+ ions (hydrogen) –Ex: lemon juice (6), stomach acid (1.5), acid rain (4.5), normal rain (6) Facts about Acids Acids turn litmus paper RED and usually taste SOUR.Acids turn litmus paper RED and usually taste SOUR. You eat acids daily (coffee, vinegar, soda, citrus fruits, etc…)You eat acids daily (coffee, vinegar, soda, citrus fruits, etc…)

ACIDS & BASES Bases: always (almost) end with -OH because of the excess of hydroxide ions (Oxygen & Hydrogen)Bases: always (almost) end with -OH because of the excess of hydroxide ions (Oxygen & Hydrogen) –EX: oven cleaner, bleach, ammonia, sea water, blood Facts about Bases Bases turn litmus BLUE.Bases turn litmus BLUE. Bases usually feel SLIPPERY to touch and taste BITTER.Bases usually feel SLIPPERY to touch and taste BITTER.

Neutralization Reactions Neutralization Reactions When an acid reacts with a base to produce a salt and water.When an acid reacts with a base to produce a salt and water.

pH SCALE measures degree of substance alkalinity or aciditymeasures degree of substance alkalinity or acidity Ranges from 0 to 14Ranges from 0 to 14 0 – 5 strong acid0 – 5 strong acid 6-7 neutral6-7 neutral 8-14 strong base8-14 strong base

The goal of the body is to maintain HOMEOSTASIS (neutrality) – to do this when pH is concerned, we add weak acids & bases to prevent sharp changes in pH.The goal of the body is to maintain HOMEOSTASIS (neutrality) – to do this when pH is concerned, we add weak acids & bases to prevent sharp changes in pH. These are called BUFFERSThese are called BUFFERS