Acids and Bases

Indentifying Properties Acids Sharp, sour, or tart taste Turn litmus paper red Phenolphthalein (liquid indicator) remains clear React with metals to form H 2 (g) Bases Slippery feeling Bitter taste Turn litmus paper blue Phenolphthalein turns hot pink

Chemical Composition Acids Composed of one (or more) hydrogen ion(s) and an anion (-) Generate hydronium ions: H 3 O + Bases Composed of one (or more) hydroxide ion(s) and a cation (+) Generate hydroxide ions: OH -

Electrolytic Properties of Acids and Bases Both acids are bases can be electrolytes—they can provide a pathway for electricity to flow through a water solution. The stronger the acid or base, the more it dissociates, the better its electrolytic capabilities. Complete dissociation Partial dissociation

Strong vs. Weak Acids & Bases Acids Strong – hydrochloric (aka muriatic) acid HCl – Nitric acid HNO 3 – Sulfuric acid H 2 SO 4 Weak – Acetic acid HC 2 H 3 O 2 – Citric acid HC 6 H 7 O 7 Bases Strong – Ammonium hydroxide NH 4 OH – Calcium hydroxide Ca(OH) 2 – Magnesium hydroxide Mg(OH) 2 – Barium hydroxide Ba(OH) 2 Weak – Sodium bicarbonate NaHCO 3

pH Scale Used to show relative strength of acids and bases Ranges from 0 to Acid Neutral Base

Arrhenius Definitions AcidBase Any substance that, in solution, increases the hydronium ion concentration A substance that, in solution, increases the hydroxide ion concentration

Acid-Base Reactions aka Neutralization Reactions These occur when an acid reacts with a base. Often times a neutralization reaction will produce an ionic compound (a salt) and H 2 O. Ex: HCl + NaOH NaCl + H 2 O BaseAcidSaltWater