Presentation on theme: "Acids & Bases They are everywhere.. In your food In your house EVEN IN YOU!!!!!"— Presentation transcript:
Acids & Bases They are everywhere.. In your food In your house EVEN IN YOU!!!!!
What is an acid? An acid is a solution that has an excess of H+ ions. It comes from the Latin word acidus that means "sharp" or "sour". The more H + ions, the more acidic the solution.
Properties of an Acid Tastes Sour Conduct Electricity Corrosive, which means they break down certain substances. Many acids can corrode fabric, skin,and paper Some acids react strongly with metals Turns blue litmus paper red Picture from BBC Revision Bites http://www.bbc.co.uk/schools/ks3bitesize/science/chemistry/acids_b ases_1.shtml http://www.bbc.co.uk/schools/ks3bitesize/science/chemistry/acids_b ases_1.shtml
Uses of Acids Acetic Acid = Vinegar Citric Acid = lemons, limes, & oranges. It is in many sour candies such as lemonhead & sour patch. Ascorbic acid = Vitamin C which your body needs to function. Sulfuric acid is used in the production of fertilizers, steel, paints, and plastics. Car batteries
Arrhenius Acids and Bases Acids produce H + in aqueous solutions water HCl H + (aq) + Cl - (aq) Bases produce OH - in aqueous solutions water NaOH Na + (aq) + OH - (aq)
Acids þ Produce H + (as H 3 O + ) ions in water þ Produce a negative ion (-) too þ Taste sour þ Corrode metals þ React with bases to form salts and water
What is a base? A base is a solution that has an excess of OH- ions. Another word for base is alkali. Bases are substances that can accept hydrogen ions
Properties of a Base Feel Slippery Taste Bitter Corrosive Can conduct electricity. (Think alkaline batteries.) Do not react with metals. Turns red litmus paper blue.
Uses of Bases Bases give soaps, ammonia, and many other cleaning products some of their useful properties. The OH- ions interact strongly with certain substances, such as dirt and grease. Chalk and oven cleaner are examples of familiar products that contain bases. Your blood is a basic solution.
Bases Produce OH - ions in water Taste bitter, chalky Are electrolytes Feel soapy, slippery React with acids to form salts and water
Learning Check AB1 Describe the solution in each of the following as: 1) acid 2) base or 3)neutral. A. ___soda B. ___soap C. ___coffee D. ___ wine E. ___ water F. ___ grapefruit
Solution AB1 Describe each solution as: 1) acid 2) base or 3) neutral. A. _1_ soda B. _2_ soap C. _1_ coffee D. _1_ wine E. _3_ water F. _1_ grapefruit
Learning Check AB2 Identify each as characteristic of an A) acid or B) base ____ 1. Sour taste ____ 2. Produces OH - in aqueous solutions ____ 3. Chalky taste ____ 4. Is an electrolyte ____ 5. Produces H + in aqueous solutions
Solution AB2 Identify each as a characteristic of an A) acid or B) base _A_ 1. Sour taste _B_ 2. Produces OH - in aqueous solutions _B_ 3. Chalky taste A, B 4. Is an electrolyte _A_ 5. Produces H + in aqueous solutions
Some Common Acids HCl hydrochloric acid HNO 3 nitric acid H 3 PO 4 phosphor ic acid H 2 SO 4 sulfur ic acid CH 3 COOH acet ic acid
Learning Check AB3 Give the names of the following A. HBr (aq)1. bromic acid 2. bromous acid 3. hydrobromic acid B. H 2 CO 3 1. carbonic acid 2. hydrocarbonic acid 3. carbonous acid
Solution AB3 A. HBr3. hydrobromic acid The name of a nonoxy acid begins with the prefix hydro- and ends with -ic acid. In a nonoxy acid, the negative anion end in -ide. B. H 2 CO 3 1. carbonic acid The name of an oxyacid is named with the stem of the anion (carbonate) changed to -ic acid
Some Common Bases NaOHsodium hydroxide KOH potassium hydroxide Ba(OH) 2 ________________________ Mg(OH) 2 ________________________ Al(OH) 3 aluminum hydroxide
Learning Check AB4 Match the formulas with the names: A. ___ HNO 2 1) hydrochloric acid B. ___Ca(OH) 2 2) sulfuric acid C. ___H 2 SO 4 3) sodium hydroxide D. ___HCl4) nitrous acid E. ___NaOH5) calcium hydroxide
Solution AB4 Match the formulas with the names: A. _4__ HNO 2 1) hydrochloric acid B. _5__Ca(OH) 2 2) sulfuric acid C. _2__H 2 SO 4 3) sodium hydroxide D. _1__HCl4) nitrous acid E. _3__NaOH5) calcium hydroxide
Learning Check AB5 Acid, Base Name or Salt CaCl 2 _______________________ KOH_______________________ Ba(OH) 2 ______ _________________ HBr_______________________ H 2 SO 4 ________________________
Solution AB5 Acid, Base Name or Salt CaCl 2 saltcalcium chloride KOHbasepotassiuim hydroxide Ba(OH) 2 basebarium hydroxide HBracidhydrobromic acid H 2 SO 4 acidsulfuric acid
Bronsted-Lowry Acids Acids are hydrogen ion (H +) donors Bases are hydrogen ion (H + ) acceptors HCl + H 2 O H 3 O + + Cl - donor acceptor + - +
pH Scale pH is a measure of how acidic or basic a solution is. The pH scale ranges from 0 to 14. Acidic solutions have pH values below 7 A solution with a pH of 0 is very acidic. A solution with a pH of 7 is neutral. Pure water has a pH of 7. Basic solutions have pH values above 7.
pH Scale A change of 1 pH unit represents a tenfold change in the acidity of the solution. For example, if one solution has a pH of 1 and a second solution has a pH of 2, the first solution is not twice as acidic as the second— it is ten times more acidic.
Acid – Base Reactions A reaction between an acid and a base is called neutralization. An acid-base mixture is not as acidic or basic as the individual starting solutions.
Acid – Base reactions Each salt listed in this table can be formed by the reaction between an acid and a base.