Things to Ponder The nicest thing about the future is that it always starts tomorrow.

Deal with the faults of others as gently as with your own!

Acid-Bases Lesson2

Acid Reactions

Problem How would you prepare 5.0 L of a 1.5 M solution of glucose? First chemical formula for glucose is ? C 6 H 12 O 6

Work Find the molar mass of glucose Molar mass of glucose = g C 6 H 12 O 6

Work Cont 1.5 mol C 6 H 12 O g C 6 H 12 O L solution 1 L solution 1 mol C 6 H 12 O 6 Answer= g C 6 H 12 O 6 Write as Put g C 6 H 12 O 6 in a 5.0 L container and add enough water to get 5.0 L.

Properties of Acids and Bases Although taste is not a safe way to classify acids and bases, you probably are familiar with the sour taste of acids.

Acid Contain hydrogen ion (H+) pH < 7 Taste sour Electrolyte Reacts with metals that are more reactive than H+. [acidus is latin for sour]

Examples of Acids Lemon juice Vinegar (Acetic Acid) Hydrochloric Acid

Metal Activity Chart Li K Ba Sr Ca Na Mg Al Mn Zn Cr Most Active Fe Cd Co Ni Sn Pb H Cu Bi Sb Hg Ag Pt Au Least Active

Corrosion Oxidation of metals or substances.

Bases Contain hydroxide ion (OH - ) pH > 7 Taste bitter Feels slippery Weak electrolyte

Examples Soaps Baking soda Sodium Hydroxide

Alkaline solutions Another name for basic solutions

Hydronium ion H 3 O + Is a H + attached to a water molecule. Results in an acidic hydrogen

Monoprotic acids Have only one acidic hydrogen. (Ex: HCl)

Diprotic acid Has 2 acidic hydrogens.

Triprotic acid Contains 3 acidic hydrogens.

ACID-BASE THEORIES The most general theory for common aqueous acids and bases is the BRØNSTED - LOWRY theoryThe most general theory for common aqueous acids and bases is the BRØNSTED - LOWRY theory ACIDS DONATE H + IONSACIDS DONATE H + IONS BASES ACCEPT H + IONSBASES ACCEPT H + IONS

Bronsted - Lowrey Came up with a theory that states an acid is a H + donor, a base as a H + acceptor.

pH range 0-14

Common acids/bases

K w - ion - product constant for H 2 O = 1 x (mol / L) 2

K w = [H + ] x [OH - ] Remember K w = 1 x (mol / L) 2

Problem Find the [ OH - ] if the [ H + ] = 1 x M Work 1 x (mol / L) 2 = 1 x M x [ OH - ] Answer: [ OH - ] = 1 x M

Problem Find the [ H + ] if the [OH - ] = 1 x M. Work 1 x (mol / L) 2 = 1 x M x [ H + ] Answer: [ H + ] = 1 x M

pH = - log [H +]

Note: Must be the hydrogen ion NOT the hydroxide. Number used to denote the hydrogen - ion concentration, of a solution it is the negative logarithm of the H + ion concentration of a solution

Problem: Find the pH if the [H + ] = 1 x M. Is this an acid or base. Answer Base

Work Using calculator if you have the [H + ] put this number in then hit LOG and multiply by -1. pH = - ( 1 x M) hit LOG Answer= pH = 10 therefore this is a base.