Chemical Reactions 5 - Acids and Bases
Alkaline
relating to or containing an alkali (base); having a pH greater than 7
pH scale
A range of 0-14 to show the concentration of hydrogen ions in a solution Tells how strong or weak acids or bases are <7 acid, 7 neutral, >7 basic (alkaline)
Neutralization
A reaction of an acid with a base, yielding a solution that is not as acidic or basic as the starting solutions were
Base
A substance that tastes bitter, feels slippery, and turns red litmus paper blue They have pH levels above 7.
Acid
A substance that tastes sour, reacts with metals and carbonates, turns blue litmus red. They have pH levels lower than 7.
Acids Used in Industry
Muriatic (HCl) - cleans concrete and bricks Sulfuric - car batteries, acid rain Nitric - plant fertilizers Phosporic - plant fertilizers, Coke and Pepsi
Common Bases
Soap Shampoo Detergent Tonic water Ammonia Sodium hydroxide
Blue litmus paper
Stays blue in the presence of bases but turns red with acids
Red litmus paper
Stays red in the presence of acid but turns blue with bases
Four Properties of Bases
Bitter taste Slippery feel pH >7 turn red litmus paper blue
Indicators
Compounds that change color in the presence of an acid or a base Examples: pH paper, litmus paper, phenolphthalein solution, cabbage juice, tea
Hydrogen
Gas produced when acids react with metals
Neutral
Substances that are neither acidic nor basic Example: water
Four Properties of Acids
Taste sour pH < 7 React with metal to produce hydrogen gas React with carbonates Turn blue litmus paper red
Litmus test
a coloring material that turns red in acid solutions and blue in alkaline solutions
Acidic
a pH below 7; contains more H+ ions than hydroxide ions (OH-)
Salts
a product (ionic compound) made from the neutralization of an acid with a base
Basic
pH above 7 (alkaline); more OH- ions than H+ ions
