Acids, Bases, and Salts

I. Properties of Acids

Sour tasteSour taste Change colors of acid-base indicators warm Change colors of acid-base indicators warm

colors– turns litmus paper colors– turns litmus paper redred Some react with active metals to release HSome react with active metals to release H22

Acid + Base Acid + Base → Salt + water→ Salt + water Conduct electric currentConduct electric current

III. Properties of Bases

Bitter tasteBitter taste Change colors of acid-base indicators cool Change colors of acid-base indicators cool

colors– turns litmus paper colors– turns litmus paper blueblue Feel slipperyFeel slippery React with acids to produce salts and waterReact with acids to produce salts and water Conduct electric currentConduct electric current

Write dissociation equation & balance

1.1. HCl HCl →→

2.2. HNOHNO33 → →

3.3. NaOH →NaOH →

4.4. Mg(OH)Mg(OH)22 → →

5.5. NaCl →NaCl →

Note any similarities between the equationsNote any similarities between the equations

IV. ARRHENIUS THEORY

Acids, bases, and salts conduct a current when Acids, bases, and salts conduct a current when dissolved in water - electrolytesdissolved in water - electrolytes

An acid produces H+ in a water solution An acid produces H+ in a water solution HCl(g) -->HCl(g) --> H+H+(aq) + Cl-(aq)(aq) + Cl-(aq)

A base produces OH- in a water solution A base produces OH- in a water solution NaOH(cr) --> Na+(aq) +NaOH(cr) --> Na+(aq) + OH-OH-(aq)(aq)

II. Naming Acids - Binary

Binary acid – contains 2 elements; hydrogen and Binary acid – contains 2 elements; hydrogen and one of the more electronegative elements.one of the more electronegative elements.

Ex. HFEx. HF

1. Begins with prefix hydro1. Begins with prefix hydro

2. Followed by root of name of second element2. Followed by root of name of second element

3. Ends with suffix -ic3. Ends with suffix -ic

hydro – fluor – ic acidhydro – fluor – ic acid HH22SS

II. Naming Acids - oxyacids

Compound of hydrogen, oxygen, and a 3Compound of hydrogen, oxygen, and a 3rdrd element element that is usually a nonmetalthat is usually a nonmetal

Formula is usually one or more H atoms followed Formula is usually one or more H atoms followed by polyatomic anionby polyatomic anion

Pg. 250Pg. 250 HNOHNO22 – nitrous acid – nitrous acid NONO22- nitrite- nitrite HNOHNO33 – nitric acid – nitric acid NONO33- nitrate- nitrate Common industrial – sulfuric, nitric, phosphoric, Common industrial – sulfuric, nitric, phosphoric,

hydrochloric, acetichydrochloric, acetic

Practice problems

Pg.250 #’s 18-22Pg.250 #’s 18-22 Pg. 596 1a,1bPg. 596 1a,1b

Strong vs. weak

Strong acids and bases fully dissociateStrong acids and bases fully dissociate Weak acids and bases partially dissociateWeak acids and bases partially dissociate

V. BRONSTED-LOWRY THEORY Acid – proton (H+) donor Base – proton acceptorAcid – proton (H+) donor Base – proton acceptor The conjugate base of an acid is the particle that remains The conjugate base of an acid is the particle that remains

after a proton is released by the acid.after a proton is released by the acid. The conjugate acid of a base is formed when the base The conjugate acid of a base is formed when the base

receives a proton from an acid.receives a proton from an acid. In the reaction In the reaction NHNH33(g) (g) ++ water(l)->NH water(l)->NH44 ++ (aq) (aq) ++ OH- OH-: : NHNH33 is the base, water is the acid, is the base, water is the acid, NH4+ is the conjugate acid, and OH- is the conjugate NH4+ is the conjugate acid, and OH- is the conjugate basebase..

NHH

HO H

H

NH H

HH OH

PRACTICE PROBLEMSWhich is the conjugate base / conjugate acid in:Which is the conjugate base / conjugate acid in:

HH33POPO44 ++ H H22O --> HO --> H33OO++ ++ H H22POPO44--

HH33O is the O is the conjugate acidconjugate acid and H and H22POPO44 is the is the conjugate base.conjugate base.

One more, which is the conjugate base / conjugate acid in:One more, which is the conjugate base / conjugate acid in:

HH44PP22OO77 + + HH22O --> HO --> H33OO++ + + HH33PP22OO77--

Again HAgain H33O is the O is the conjugate acidconjugate acid and H and H33PP22OO77- is the - is the conjugate baseconjugate base..

BRONSTED-LOWRY Acid Base Reactions HF + HHF + H22O O → F- + H→ F- + H33OO++

Subscripts designate 2 conjugate acid base pairsSubscripts designate 2 conjugate acid base pairs HF + HHF + H22O O → F- + H→ F- + H33OO++

acidacid11 base base22 base base11 acid acid22

Strength of conjugate acid and base – strong acid Strength of conjugate acid and base – strong acid – weak conj. Base. Reactions favors direction that – weak conj. Base. Reactions favors direction that produces weaker acids and basesproduces weaker acids and bases

Amphoteric

Can act as acid or base (HCan act as acid or base (H22O)O)

HH22SOSO44 + H + H22O O →→

basebase NHNH33 + H + H22O →O →

acidacid

BRONSTED-LOWRY THEORY

MonoMonoprotic acid – donates only one protonprotic acid – donates only one proton

PolyPolyprotic acid – donates more than one protonprotic acid – donates more than one proton

DiDiprotic – donates 2 protonsprotic – donates 2 protons

TriTriprotic – donates 3 protonsprotic – donates 3 protons All polyprotic ionize in stepsAll polyprotic ionize in steps HH33POPO44(aq) pg. 601 #3a,3b(aq) pg. 601 #3a,3b

LEWIS THEORY

Lewis focused on an electron transfer rather Lewis focused on an electron transfer rather than a proton transfer.than a proton transfer.

Lewis described an acid as an electron-pair Lewis described an acid as an electron-pair acceptor and a base as an electron-pair acceptor and a base as an electron-pair donor.donor.

An acid or base in Arrhenius theory is the An acid or base in Arrhenius theory is the same under the Lewis and Bronsted-Lowry same under the Lewis and Bronsted-Lowry theories.theories.

MORE PRACTICE PROBLEMS

CLASSIFY THE FOLLOWING CLASSIFY THE FOLLOWING SUBSTANCES AS LEWIS ACIDS OR SUBSTANCES AS LEWIS ACIDS OR BASES.BASES.

a. Cl- b. Al+ c. Br- d. I+a. Cl- b. Al+ c. Br- d. I+

a and c = Lewis Base a and c = Lewis Base

b and d = Lewis Acidb and d = Lewis Acid