Identifying Acids and Bases pH Formula Name Characteristics Reaction to other substances

Identifying Acids, Bases and Salts 2. By their formula: Compound Ions Type HX H+  X- acid YOH Y+  OH- base YX Y+  X- salt

Identifying Acids Most acids begin with an H: HCl HClO3 H3BO3 HNO3 H2SO4 HN Exceptions: water H20 and acids containing carbon: CH3COOH An acid is a solution where there are more H + than OH ions. You can often see this in the name –-- HCl (aq) which is hydrochloric acid.

Identifying Acids Acids behave like acids only when dissolved in water. It is only in solution where they dissociate and give up their protons (H+). Therefore, acids are often written with subscript (aq) = aqueous solution eg HCl (aq)

Binary Acids Binary Acids Hydrogen is bonded to a second non-metal: HCl, HF, HBr, HI, H2S

Naming Acids Acids must be in solution. The formula HF does not indicate state of matter: solid compound: hydrogen fluoride in solution: hydrofluoric acid.

Naming Acids If in aqueous form, use: Hydro……….ic acid eg. HCl Hydrochloric acid If no state is given, use: Hydrogen…..….-ide eg. HCl Hydrogen chloride

Naming Binary Acids Name the acid HI (Hydrogen Iodide): Start with hydro- Take anion root -iod add -ic Add to end acid Hydroiodic acid

Naming Binary Acids Start with Hydro- Add anion root Sulfur- Add -ic Name H2S (hydrogen sulfide) as an acid in solution: Start with Hydro- Add anion root Sulfur- Add -ic Add Acid Hydrosulfuric Acid

Naming Acids with Oxygen (polyatomic ions) Do not add hydrogen to these names Naming depends the anion (-ate, -ite, per-) If ion ends in "-ate“, add “ic” Eg. NO3 is called nitrate, So HNO3 (hydrogen nitrate) will be nitric acid Eg: hydrogen perchlorate ……HClO4 (aq) will be perchloric acid

Naming Acids Example SO4 2- Sulfate H2SO4 Hydrogen sulfate or H2SO4 (aq) Sulfuric acid

Naming Acids CH3COO- acetate ion CH3COOH hydrogen acetate CH3COOH (aq) acetic acid BrO3- bromate HBrO3 hydrogen bromate HBrO3 (aq) bromic acid

Naming Acids: Polyatomic with Oxygen Polyatomic ion ending in “–ite”, The acid will end in "-ous." Example: ClO2- anion is chlorite, HClO2 is called chlorous acid

Naming Acids SO3 2- Sulfite ion H2SO3 hydrogen sulfite H2SO3 (aq) sulfurous acid

Naming Acids: Polyatomic with Oxygen Example, the perchlorate ion is ClO4-, HClO4 (aq) is called perchloric acid.

Naming Acids Summary Binary Acids: hydro……ic acid Containing Polyatomic ion with Oxygen: Anion Acid Ends with –ate ……………ic acid Ends with –ite ………..…ous acid Starts with per- per…………ic acid Starts with hypo- hypo……..ous acid

Common Acids Hydrochloric acid – stomach acid (HCl) Muriatic acid – pool disinfectant (also HCl) Acetic acid - vinegar , CH₃COOH Citric acid – lemon juice, C₆H₈O₇ Lactic acid - fermented milk CH₃CHCO₂H Ascorbic acid – vitamin C, C6H8O6 sufuric acid – battery acid, H2SO4 Nitro-hydrochloric acid -Aqua regia

Bases Bases can be identified by their chemical formula: The chemical formula of a base usually ends with hydroxide ion (-OH). Bases usually start with a metal or NH4 + See page 227

Bases Bases, like acids, behave like bases only when dissolved in water. Therefore, bases are often written with subscript (aq) = aqueous = in solution

Naming Bases- Strong Most strong bases contain hydroxide (OH), a polyatomic ion. Therefore, the naming strong bases follows same rules for naming ionic compounds: anion + cation NaOH is sodium hydroxide, KOH is potassium hydroxide, Ca(OH)2 is calcium hydroxide.

Naming Bases-Weak Weak bases made of ionic compounds are also named using the ionic naming system. NH4OH is ammonium hydroxide.

Common Household Bases NaOH(aq) draino, caustic soda, lye, soap NaClO (aq) sodium hypochlorite-bleach Mg(OH)2(aq) antacid Ca (OH)2(aq) slaked lime NH4OH(aq) ammonium hydroxide, cleaning products Na2CO3 sodium carbonate (washing soda) NaHCO3 sodium bicarbonate (baking soda) See page 227

Fun Facts about Bases Sodium hydroxide is used to make soap. Ammonium hydroxide is used to remove ink from clothes and remove grease from windows. Bases are molecules which attract hydrogen ions from acidic molecules. All alkalies (basic, ionic salt of an alkali metal or alkaline earth metal) are bases, but not all bases are alkalies. Baking soda can be used to fight fires by obstructing the flow of oxygen.

Properties of Acids and Bases See page 229 Take the Section 5.1 Quiz