[...]... ­BrønstedL ­ owry theory of acids and bases What are Acids and Bases?   21 Lewis Acids and Bases In 1923, the same year that Brønsted and Lowry came up with their idea of what acids and bases were, an American chemist named Gil-­ bert Newton Lewis began to work on his own ­acid-­base theory Lewis defined acid as any substance that accepted an electron pair A base, on the other hand, is any substance that... very careful around strong bases such as oven cleaners, which contain lye (sodium or potassium hydroxide), or strong acids such as sulfuric acid Bases change pink litmus blue and react with acids to form a salt and water Bases are also called ­alkalis Acids and bases are almost always found as aqueous ­solutions— t ­ hat is, dissolved in water Solutions of both acids and bases are called electrolytes... is called ­polybasic Arrhenius’ theory explained a lot about acids and bases, but it did not explain everything Not all bases release hydroxide ions In fact, one of the most commonly used bases baking soda What are Acids and Bases?   19 (NaHCO3)—does not contain any hydroxide ions So why does it act as a ­base? Brønsted-­Lowry Acids and Bases In 1923, two scientists, working independently, came up... erin stops working and no longer relieves the patient’s chest pain 10   acids and bases According to the Duke University study, there is a finite amount of the enzyme that breaks down the nitroglycerin in the mitochon-­ dria Once the enzyme is “used up,” nitroglycerin no longer works for that ­patient EVERYDAY ACIDS AND BASES These are some of the more exotic examples of acids and bases As mentioned... next to her and who also turned into a soap mummy is sometimes displayed in the Smithsonian Institute in Washington, D.C., too Not surprisingly, he is called the “Soap Man.” A World of Acids and Bases 11 Figure 1.4  Above are some common household acids and bases The items on the ­left—­vitamin C, aspirin, and ­ vinegar—­contain acids The items on the right— ­milk of magnesia, baking soda, and drain... ­properties ­that ­define ­them ­as acids ­ For ­example, acids ­can ­dissolve ­some ­metals, ­such ­as ­lead and ­zinc ­ They ­change ­litmus ­(a ­dye ­made ­from ­lichens) ­from ­blue ­to ­pink, ­ and ­they ­react ­with bases ­to ­form ­a ­salt and ­ ­ water Bases ­have ­specific ­properties ­that ­mark ­them ­as bases, ­too ­ Bases ­ taste ­ bitter, ­ but ­ most ­ bases ­ are ­ not ­ food, ­ so... which gives them their tart flavor Vinegar is a 5% solution of ethanoic acid (also called acetic acid) and ­water Like acids, bases have many important uses Ammonia, soap, and other cleaners work to dissolve dirt because of their basic EC_AcidsBases_rep09.indd 11 11/16/09 2:08:37 PM 12   acids and bases Acid-­Washed ­Jeans The term “acid” is sometimes used in misleading ways Take ­acid-­washed jeans,... would not) Aqua regia, or “royal water,” on the other hand, could dissolve gold It turns out that the alchemists’ aqua regia was a mixture of concentrated hydrochloric and nitric acids Either of these acids alone will not affect gold, but a mixture of the two dissolves the precious ­metal EC_AcidsBases_rep09.indd 21 11/16/09 2:08:39 PM 22   acids and bases Gilbert Newton Lewis devised what would come to... “both.” Water is the most common amphoteric substance, but amino acids, proteins, and some metal oxides—such as aluminum oxide (Al2O3) and zinc oxide (ZnO), for example—can also act as amphoteric ­substances 3 determining acids and bases T he ­simplest acids ­are ­composed ­of ­just ­two ­elements ­Such acids ­ are ­called ­binary acids ­When ­naming ­a ­binary ­acid, ­the ­prefix ­ hydro- ­is ­used... substances that can be either acidic or basic They are used to adjust the chemical composition of soil to enable the plants to grow So people use acids and bases every day, but how can you tell if a substance is an acid or a ­base? 2 What are acids and bases? A cids and bases ­are ­determined ­by ­their ­properties ­The ­word ­ acid ­comes ­from ­the ­Latin ­word ­acidus, ­which ­means ­“sour.” ­ For ­ example, . and may no longer be valid. A World of Acids and Bases 1 What are Acids and Bases? 13 Determining Acids and Bases 26 Acids and Bases in Chemistry 41 Acids and Bases in Industry 55 Acids and Bases. taste the same way. Bases taste bitter, feel slippery, and react with acids. Without bases, cakes would be hard and flat, and laundry detergent would not clean. Both acids and bases can change. aspirin, and vinegar—contain acids. The items on the right— milk of magnesia, baking soda, and drain cleaner—contain bases. EC_AcidsBases_rep09.indd 11 11/16/09 2:08:37 PM 12 acids and bases