Acids Bases Acids vacids are sour tasting v
Acids & Bases Acids: vacids are sour tasting v. Arrhenius acid: acid Any substance that, when dissolved in water, increases the concentration of hydronium ion (H 3 O+) v. Bronsted-Lowry acid: acid A proton donor v. Lewis acid: acid An electron acceptor Bases: vbases are bitter tasting and slippery v. Arrhenius base: base Any substance that, when dissolved in water, increases the concentration of hydroxide ion (OH-) v. Bronsted-Lowery base: base A proton acceptor v. Lewis acid: acid An electron donor
ELECTROLYTES Electrolytes are species which conducts electricity when dissolved in water. Acids, Bases, and Salts are all electrolytes. Salts and strong Acids or Bases form Strong Electrolytes. Salt and strong acids (and bases) are fully dissociated therefore all of the ions present are available to conduct electricity. HCl(s) + H 2 O H 3 O+ + Cl. Weak Acids and Weak Bases for Weak Electrolytes. Weaks electrolytes are partially dissociated therefore not all species in solution are ions, some of the molecular form is present. Weak electrolytes have less ions avalible to conduct electricity. NH 3 + H 2 O NH 4+ + OH-
Acids & Bases STRONG _ completely ionized _ strong electrolyte _ ionic/very polar bonds Strong Acids: HCl. O 4 H 2 SO 4 HI HBr HCl HNO 3 vs WEAK _ partially ionized _ weak electrolyte _ some covalent Strong Bases: Li. OH Na. OH KOH Ca(OH)2 Sr(OH)2 Ba(OH)2
Acids & Bases For the following identify the acid and the base as strong or weak. a. Al(OH)3 + HCl Weak base Strong acid b. Ba(OH)2 + Strong base HC 2 H 3 O 2 Weak acid c. KOH + H 2 SO 4 Strong base Strong acid d. NH 3 + H 2 O Weak base Weak acid
Acids & Bases For the following predict the product. To check your answer left click on the mouse. Draw a mechanism detailing the proton movement. a. Al(OH)3 + 3 HCl Al. Cl 3 + 3 H 2 O b. Ba(OH)2 + 2 HC 2 H 3 O 2 Ba(C 2 H 3 O 2)2 + 2 H 2 O c. 2 KOH + H 2 SO 4 K 2 SO 4 + 2 H 2 O d. NH 3 + H 2 O NH 4+ + OH-
Acids & Bases For the following Identify the conjugate acid and the conjugate base. The conjugate refers to the acid or base produced in an acid/base reaction. The acid reactant produces its conjugate base (CB). CB a. Al(OH)3 + 3 HCl Al. Cl 3 + 3 H 2 O CA CB b. Ba(OH)2 + 2 HC 2 H 3 O 2 Ba(C 2 H 3 O 2)2 + 2 H 2 O CB c. 2 KOH + H 2 SO 4 K 2 SO 4 + 2 H 2 O CB d. NH 3 + H 2 O NH 4+ + OHCA CB CA CA
p. H A measure of the hydronium ion • The scale for measuring the hydronium ion concentration [H 3 O+] in any solution must be able to cover a large range. A logarithmic scale covers factors of 10. The “p” in p. H stands for log. • A solution with a p. H of 1 has [H 3 O+] of 0. 1 mol/L or 10 -1 • A solution with a p. H of 3 has [H 3 O+] of 0. 001 mol/L or 10 -3 • A solution with a p. H of 7 has [H 3 O+] of 0. 0000001 mol/L or 10 -7 p. H = - log [H 3 O+]
The p. H scale ranges from 1 to 10 -14 mol/L or from 1 to 14. p. H = - log [H 3 O+] 1 2 3 4 5 6 7 8 9 10 11 12 13 14 acid neutral base
Manipulating p. H Algebraic manipulation of: p. H = - log [H 3 O+] allows for: [H 3 O+] = 10 -p. H If p. H is a measure of the hydronium ion concentration the same equations could be used to describe the hydroxide (base) concentration. [OH-] = 10 -p. OH = - log [OH-] thus: p. H + p. OH = 14 ; the entire p. H range!
PRACTICE PROBLEMS 3. What is the molar concentration of hydronium ion in a solution of p. H 8. 25? 5. 623 x 10 -9 M 4. What is the p. H of a solution that has a molar concentration of hydronium ion of 9. 15 x 10 -5? p. H = 4. 0
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