Acids and bases

What is an acid? An acid is any compound that increases the number of hydrogen ions (H+) when dissolved in water Solution tastes sour Can change the color of certain compounds

Properties of acids Many acids are corrosive (destroy body tissue and clothing) Many are also poisonous Solutions of acids conduct an electric current Turns blue litmus paper red-associated with the color RED

Uses of acids Sulfuric acid – industrial chemical used in the production of Metals Paper Paint Detergents Fertilizers Car batteries Nitric acid Rubber Plastics

Uses of acids Hydrochloric acid Metals Keep swimming pools free of algae Stomach acid – aids in digestion Citric acid/ascorbic acid Orange juice Carbonic acid/phosphoric acid “bite” to soft drinks

What is a base? A base is any compound that increases the number of hydroxide ions (OH- ) when dissolved in water Solution tastes bitter, feels slippery Can change the color of certain compounds

Properties of bases Many bases are corrosive Solutions of bases can conduct an electric current Changes the color of litmus paper blue- Associated with the color BLUE

Uses of bases Sodium hydroxide used in Soap Paper Oven cleaners Products to unclog drains Calcium hydroxide Cement Mortar Plaster

Uses of bases Ammonia Household cleaners Production of fertilizers Magnesium hydroxide/aluminum hydroxide Antacids to treat heartburn

Acids and bases neutralize one another Acids and bases neutralize one another because of the H+ of the acid and the OH- of the base react to form water, H2O. If the water is evaporated, these ions join to form a compound called a salt.

Indicators such as litmus paper, and red cabbage juice, can identify whether a solution contains an acid or base The pH of a solution is a measure of the hydronium ion concentration in the solution A pH of 7 is neutral, meaning neither acidic or basic Basic solutions have a pH greater than 7 Acidic solutions have a pH less than 7 pH scale

pH Scale