Acids and Bases l 3 definitions for acids

Acids and Bases l 3 definitions for acids and bases – – – l Must be in solution – l Arrhenius Bronsted-Lowry Lewis Most often dissolved in water (aqueous) Inorganic and Organic

Naming Acids-Binary l l l Made of just two elements Element 1 is always hydrogen Element 2 most often a halogen Prefix is hydro. Root is of the non hydrogen element Suffix is –ic

Binary Acids l HCl – l HF – l Hydrofluoric HI – l Hydrochloric Hydroiodic HBr – Hydrobromic

Ternary/Oxyacid l l l Have 3 elements Hydrogen, oxygen, nonmetal All organic acids fall in this category

Naming Ternary Acids l DO NOT USE PREFIX OF HYDRO – l l Only used for binary acids Find polyatomic ion (pg 210) Suffix –ate ic Suffix –ite ous Listed on pg 455

Strong Acids: Write the formula for the following acids Chloric acid l Hydrobromic acid l Hydrochloric acid l Hydroiodic acid l Nitric acid l Perchloric acid l Sulfuric acid l HCl. O 3 l HBr l HCl l HI l HNO 3 l HCl. O 4 l H 2 SO 4 l

Common acids used (Not strong) l l l Acetic (most common organic acid – used in vinegar) Carbonic (used in soft drinks) Phosphoric (used in fertilizer and animal feed as well as flavoring and cleaning agents)

Arrhenius (Protonic) Acid l l One or more H atoms Donates the H when in solution – l Will form a hydronium ion (H 3 O+) Most basic definition of an acid

Properties of Arrhenius Acids 1. 2. 3. 4. 5. 6. Sour taste Change litmus paper blue to red React with metal to release hydrogen gas React with oxides to form salts React with salts to form a new salt and acid Solutions will conduct electricity

3. React with metals l 2 H 3 O+(aq) + Zn(s) Zn 2+(aq)+H 2(g)+ 2 H 2 O(l) l 2 HCl(aq) + Zn(s) Zn. Cl 2(aq) + H 2(g)

Strong acids l Strong acids completely ionize – l Once the acid is placed into solution, all is broken into a H+ (becomes H 3 O+) and an anion Weak acids do not completely ionize

Polyprotic acids l l Have more than one H+ to donate to the solution Diprotic acids – – l Carbonic acid (H 2 CO 3) Sulfuric acid (H 2 SO 4) Triprotic acid – Phosphoric acid (H 3 PO 4)

Arrhenius Base l l Often called a hydroxide base Releases a Hydroxide ion when in solution Often have a alkali or an alkaline earth metal Alkali bases – l Li. OH, Na. OH, KOH Alkaline Earth bases – Mg(OH)2, Ca(OH)2, Sr(OH)2

Hydroxide bases 1. 2. 3. 4. Bitter taste Change litmus paper red to blue Neutralize aqueous acidic solutions to form water and an aqueous salt Solutions conduct electricity

3. Neutralize l l l HCl(aq) + Na. OH(aq) Na. Cl(aq) + H 2 O Ionic equation H+ + Cl- + Na+ + OH- Na+ + Cl- + H 2 O Net ionic equation H+ + OH- H 2 O

Bronsted Lowry Acid l l l Anything that donates a proton into solution Very similar to the Arrhenius definition Major difference is that we will not focus on the formation of hydronium

Bronsted Lowry Base l l Anything that accepts a proton Will not focus on hydroxide – Something can serve as a BL base without any hydroxide ions

Amphoteric substances l l l Compounds that can serve as either an acid or a base depending on what they are reacted with Water is a great example Hydroxides of the metals with high oxidation #’s (near the separation line) Act as acids with strong bases Act as bases with strong acids

Conjugate acids and bases l Conjugate acid – l What is formed from a BL base accepting a proton Conjugate base – What is formed by a BL acid donating a proton

Lewis Acid/Base l l l Accept an electron pair = acid Donate an electron pair = base May need to draw Lewis structure in order to see NH 3 + H 2 O NH 4+ + OHHCl + H 2 O Cl- + H 3 O+

Lewis Acid/Base l Show Lewis Acid and base for reaction between… – – – HI and water HNO 3 and water HCN and water