Download presentation
Presentation is loading. Please wait.
1
AP Chemistry Acids & Bases, Ksp
2
Acids and bases "ACID"--Latin word acidus, meaning sour. (lemon)
"ALKALI"--Arabic word for the ashes that come from burning certain plants; water solutions feel slippery and taste bitter. (soap)
3
Acid-base theories Arrhenius definition
Acid – donates a hydrogen ion (H+) in water Base – donates a hydroxide ion in water (OH−) This theory is limited to substances with those “parts”. Ammonia is a MAJOR exception! Acid examples: HCl, H2SO4 Base examples: NaOH, KOH, Ba(OH)2
4
What is the Bronsted Lowry Theory | The Chemistry Journey
5
Acid-base theories Bronsted-Lowry Definition
Acid – donates a proton (H+) in water Base – accepts a proton in water This theory is better; it explains ammonia as a base! This is the main theory that we will use for our acid/base discussion.
6
Acid-base theories Lewis Definition Acid – accepts an electron pair
Base – donates an electron pair This terminology is not as widely used as it used to be because it is too general. Instead, we focus on coordination complexes, which are products of Lewis Acid-Base reactions.
7
THE BRONSTED-LOWRY CONCEPT OF ACIDS AND BASES
Using this theory, you should be able to write weak acid/base dissociation equations and identify acid, base, conjugate acid and conjugate base. conjugate acid-base pair – A pair of compounds that differ by the presence of one H+ unit
8
Neutral compound as an acid:
HNO3 + H2O H3O+ + NO3 − Conj. Acid Conj. Base ACID BASE
9
cation as an acid: NH4+ + H2O H3O+ + NH3 Conj. Acid Conj. Base ACID
10
Anion as an acid: H2PO4− + H2O H3O+ + HPO42− ACID BASE Conj. Acid
In each of the acid examples notice the formation of H3O+ – this species is named the “hydronium ion” It lets you know that the solution is acidic!
12
Basic solutions Label the acid, base, conjugate acid, and conjugate base. NH3 + H2O NH4+ + OH- CO32- + H2O HCO3- + OH- PO43- + H2O OH- + HPO42- Notice the formation of OH- in each of the alkaline examples. This species is named the hydroxide ion. It lets you know the resulting solution is basic!
14
Conjugate Acids and Bases | The Chemistry Journey
15
Amphoteric molecules Amphoteric --molecules or ions that can behave as EITHER acids or bases; water, anions of weak acids (look at the examples above—sometimes water was an acid, sometimes it acted as a base)
16
Neutralization reaction
Video containing information about water as an amphoteric molecule.
17
Bell work – 11/29/16 For the following reactions, identify the acid, base, conjugate acid, and conjugate base. C2H5OH + H2O H3O+ + C2H5O- ACID BASE CA CB HPO42- + NH4+ NH3 + H2PO4- BASE ACID CB CA
18
pH Scale
19
pH Scale 7 14
20
Why does [H+] = [OH-] at pH 7?
21
pH and pOH pH [H+] (M) [OH-] (M) pOH 7 6 3 12
22
pH and pOH What is the pattern between pH and [H+]?
What is the relationship between [H+] and [OH-]? How is pH related to pOH?
23
Calculating pH
24
Calculating ph pH = – log[H+] pOH = – log[OH–]
The pH of a solution is 3.75, what is the Hydrogen ion concentration, [H+]?
25
Examples What is the pH of a solution with a hydrogen ion concentration of 2.0 x 10-11? What is the pOH of a solution with a hydroxide ion concentration of 1.8 x 10-4? The pH of human blood was measured to be 7.41 at 25°C. Calculate the pOH, [H+], and [OH-] for the sample. 10.70 3.74 pOH = 6.59, [H+] = 3.9 x 10-8 M, [OH-] = 2.6 x 10-7 M
26
Acid and base quiz 1. OH- + HPO42- H2O + PO43-
For questions 1 and 2 identify the acid, base, conjugate acid, and conjugate base. 1. OH- + HPO42- H2O + PO43- 2. HF + NH3 NH4+ + F- For questions 3-7 Name the acid or base. H3PO HNO2 HBr LiOH Mg(OH)2 Given a pH of 9, find the [H+], pOH, and [OH-]. Is the solution acidic or basic? (show all work) If [H+] = 2.5 x 10-5, find the pH, pOH, and [OH-]. Is the solution acidic or basic? (show all work)
27
After quiz…… Predict the products for the following neutralization reactions: NaOH + HCl HBr + Mg(OH)2
28
Concentrated vs. Strong
“Concentrated” – refers to the amount dissolved in solution. “Strong” – refers to the fraction of molecules that ionize. For example, if you put a lot of ammonia into a little water, you will create a highly concentrated solution. However, since only 0.5% of ammonia molecules ionize in water, this basic solution will not be very strong.
29
Acid-Base Titration Uses a neutralization reaction to determine the concentration of an acid or base. Standard Solution: the reactant that has a known molarity Endpoint: the point at which the unknown has been neutralized.
30
Make sure you finish with correct units!!
Titration Examples Example #1) .08 L of 0.100M NaOH is used to neutralize .02 L of HCl. What is the molarity of HCl? NaOH + HCl NaCl + H2O .08 L NaOH x .100 mols NaOH x 1 mol HCl x = M 1 L NaOH mol NaOH L HCl Molarity of NaOH Molar Ratio Make sure you finish with correct units!!
31
Titration Examples (cont’d)
Example #2) A 0.1M Mg(OH)2 solution was used to titrate an HBr solution of unknown concentration. At the endpoint, 21.0 mL of Mg(OH)2 solution had neutralized 10.0 mL of HBr. What is the molarity of the HBr solution?
32
Titration Practice What is the molarity of an Al(OH)3 solution if 30.0 mL of the solution is neutralized by 26.4 mL of a 0.25 M HBr solution? A 0.3 M Ca(OH)2 solution was used to titrate an HCl solution of unknown concentration. At the endpoint, 35.0 mL of Ca(OH)2 solution had neutralized 10.0 mL of HCl. What is the molarity of the HCl solution? When 34.2 mL of a 1.02 M NaOH solution is added from a buret to mL of a phosphoric acid solution that contains phenolphthalein, the solution changes from colorless to pink. What is the molarity of the phosphoric acid?
35
HA(aq) + H2O(l) ⇄ H3O+(aq) + A– (aq)
Acid strength A strong acid completely ionizes in solution A weak acid only partially ionizes. The strength of an acid depends on the equilibrium: HA(aq) + H2O(l) ⇄ H3O+(aq) + A– (aq) If the equilibrium lies far to the left, the acid is weak (only a small percentage of the acid molecules ionize) If the equilibrium lies far to the right, the acid is strong (completely ionizes)
36
Strong acids HCl HNO3 HBr HClO4 HI H2SO4
Hydrochloric acid Nitric acid Hydrobromic acid Perchloric acid Hydriodic acid Sulfuric acid HCl HNO3 HBr HClO4 HI H2SO4 All have WEAK conjugate bases!
37
Strong acids An HCl solution contains virtually no intact HCl.
Single arrow indicates complete ionization. HCl(aq) + H2O(l) H3O+(aq) + Cl– (aq) An HCl solution contains virtually no intact HCl. The HCl has essentially all ionized to form H3O+(aq) and Cl–(aq).
38
Describing concentrations of strong acids
A 1.0 M HCl solution has an H3O+ concentration of 1.0 M. If [HCl] = 1.0 M, then [H3O+] = 1.0 M
39
Weak acids Double arrow indicates partial ionization. HF(aq) + H2O(l) ⇄ H3O+(aq) + F – (aq) An HF solution contains a large number of intact (or un-ionized) HF molecules. It also contains some H3O+(aq) and F –(aq).
40
Describing concentrations of weak acids
A 1.0 M HF solution has an [H3O+] that is much less than 1.0 M because only some of the HF molecules ionize to form H3O+. [H3O+] << [HF]
41
Some weak acids HF H2SO3 HC2H3O2 H2CO3 HCHO2 H3PO4
Hydrofluoric acid Sulfurous acid Acetic acid Carbonic acid Formic acid Phosphoric acid HF H2SO3 HC2H3O2 H2CO3 HCHO2 H3PO4 All have STRONG conjugate bases!
42
Chemistry 12.4 Strength of Acids and Bases & Intro to Ka
43
ACID IONIZATION CONSTANT (Ka)
A way to quantify the relative strength of a weak acid The equilibrium constant of the weak acid HA(aq) ⇄ H+(aq) + A–(aq) 𝐾 𝑎 = [ H 3 O + ][ A − ] [HA] = [ H + ][ A − ] [HA]
44
Ka The smaller the constant, the less the acid ionizes… ∴ the weaker the acid Hydrocyanic acid (HCN) Ka = 4.9 x 10-10 Nitrous acid (HNO2) Ka = 4.6 x 10-2 Acetic acid (HC2H3O2) Ka = 1.8 x 10-5 Hydrofluoric acid (HF) Ka = 3.5 x 10-4 Chlorous acid (HClO2) Ka = 1.1 x 10-2
45
Base ionization constant
The equilibrium expression for a base is known as Kb. This expression is used to quantify the relative strength of a weak base. B + H2O HB+ + OH- Kb = [HB+] [OH-] [B]
46
Autoionization of water (Video)
47
Autoionization of water
Fredrich Kohlraush, around 1900 found that no matter how pure water is, it still conducts a minute amount of electric current. This proves that water self-ionizes. Remember - water is amophoteric! Only about 2 in a billion water molecules are ionized at any instant!!
48
Autoionization of water
49
H+/OH- Equilibrium [H+] [OH-] [H+] [OH-]
The equilibrium expression used here is referred to as the autoionization constant for water, Kw. Kw = Kw = [H+] [OH-] [H+] [OH-]
50
Acidic or basic or neutral?
It is important to recognize the meaning of Kw. In an aqueous solution at 25°C, no matter what it contains, [H+] x [OH-] = 1.0 x There are three possible situations: A neutral solution, where [H+] = [OH-]. An acidic solution, where [H+] > [OH-]. A basic solution, where [H+] < [OH-].
51
Other temperatures… If at a temperature OTHER THAN 25°C, the Kw will be a different value. Remember that the numerical value of Keq is dependent on temperature!
52
Example 1 𝑲 𝒘 = H + OH − =𝟏.𝟎× 𝟏𝟎 −𝟏𝟒 (since it’s at 25°C)
Calculate [H+] or [OH-] as required for each of the following solutions at 25°C, and state whether the solution is neutral, acidic, or basic. 1.0 x 10-5 M OH- 1.0 x 10-7 M OH- 𝟏.𝟎× 𝟏𝟎 −𝟏𝟒 = H + (𝟏.𝟎× 𝟏𝟎 −𝟓 ) [OH-] > [H+] ∴ basic H + = 𝟏.𝟎× 𝟏𝟎 −𝟏𝟒 𝟏.𝟎× 𝟏𝟎 −𝟓 = 𝟏.𝟎× 𝟏𝟎 −𝟗 [OH-] = [H+] ∴ neutral 𝟏.𝟎× 𝟏𝟎 −𝟏𝟒 = H + (𝟏.𝟎× 𝟏𝟎 −𝟕 ) H + = 𝟏.𝟎× 𝟏𝟎 −𝟏𝟒 𝟏.𝟎× 𝟏𝟎 −𝟕 = 𝟏.𝟎× 𝟏𝟎 −𝟕
53
Example 1 𝑲 𝒘 = H + OH − =𝟏.𝟎× 𝟏𝟎 −𝟏𝟒 (since it’s at 25°C)
Calculate [H+] or [OH-] as required for each of the following solutions at 25°C, and state whether the solution is neutral, acidic, or basic. 10.0 M H+ 𝟏.𝟎× 𝟏𝟎 −𝟏𝟒 =(𝟏𝟎.𝟎) OH − [H+] > [OH-] ∴ acidic OH − = 𝟏.𝟎× 𝟏𝟎 −𝟏𝟒 𝟏𝟎.𝟎 = 𝟏.𝟎× 𝟏𝟎 −𝟏𝟓
54
At 10°C, the autoionization of water equals 2. 9 x 10-15
At 10°C, the autoionization of water equals 2.9 x Calculate [H+] and [OH-] as necessary under each of the following conditions: Calculate [H+] if [OH-] = 9.3 x 10-4 M. Is the solution acidic or basic? Calculate [H+] and [OH-] for a neutral solution. Calculate [OH-] if [H+] = 6.7 x M. Is the solution acidic or basic?
55
Calculating the ph of a weak acid
Write the balanced equation Write the equilibrium expression Use the ICE Box method I – Initial C – Change E - Equilibrium
56
Calculating the ph of a weak acid
Ex. 1 Calculate the pH of a 1.00 x 10-4 M solution of acetic acid. (Ka = 1.8 x 10-5) HC2H3O2 ⇌ H+ + C2H3O2 I 1.00 x C - x + x + x E 1.00 x 10-4 –x x x Ka = x2 we can ignore the “- x” because 1.00 x 10-4 –x it is so small. 1.8 x 10-5 = x x x 10-5 = x pH = -log (4.24 x 10-5 ) pH = 4.37 Ka = [H+][C2H3O2] [HC2H3O2 ]
57
Calculating the ph of a weak acid
The hypochlorite ion (OCl-) is a strong oxidizing agent found in household bleaches and disinfectants. It also has a relatively high affinity for protons (it is a much stronger base than Cl- for example) and forms the weakly acidic hypochlorous acid (HOCl, Ka = 3.5 x 10-8). Calculate the pH of a M aqueous solution of hypochlorous acid.
58
Calculating the ph of a weak acid
59
Calculating the ph of a weak base
The same steps are used to calculate weak bases and weak acids. (Make and ICE box). Remember! You are now calculating pOH and [OH-]!!
60
Calculating the ph of a weak base
Calculate the pH for a 15 M solution of NH3 (Kb = 1.8 x 10-5)
61
Percent ionization of a weak acid
Concentration of ionized acid (at equilibrium) % ionization= [ H + ] eq [HA] 0 ×𝟏𝟎𝟎 Concentration of acid (initially)
62
Examples of percent ionization
What is the percent ionization in a M solution nitrous acid if the [H3O+] is M? If a 2.5 M solution of nitrous acid is 1.4% ionized, what is the hydronium concentration in the solution? What is the pH of the solution?
63
Examples of percent ionization
What is the percent ionization in a M solution nitrous acid if the [H3O+] is M? If a 2.5 M solution of nitrous acid is 1.4% ionized, what is the hydronium concentration in the solution? What is the pH of the solution? % ionization DECREASES with increasing concentration of acid
64
Percent ionization of a weak acid
Concentration of ionized acid (at equilibrium) % ionization= [ H + ] eq [HA] 0 ×𝟏𝟎𝟎 Concentration of acid (initially) Determine equilibrium concentrations for all species in the ionization reaction (Use ICE table if needed). Use Ka and the equilibrium constant expression to find [H+]. Use [H+]eq and the initial acid concentration, [HA]0, to solve for percent ionization.
65
[HNO2]eq = __________________ [H+]eq = _________ [NO2-]eq = _________
Determine equilibrium concentrations for all species in the ionization reaction (Use ICE table if needed). Use Ka and the equilibrium constant expression to find [H+]. Use [H+]eq and the initial acid concentration, [HA]0, to solve for percent ionization. Find the percent ionization of a 2.5 M HNO2 solution. The Ka of nitrous acid is 4.6 x 10-4. HNO2 ⇄ H+ + NO2- [HNO2]eq = __________________ [H+]eq = _________ [NO2-]eq = _________ 2.5 – x ≈ 2.5 x x
66
Determine equilibrium concentrations for all species in the ionization reaction (Use ICE table if needed). Use Ka and the equilibrium constant expression to find [H+]. Use [H+]eq and the initial acid concentration, [HA]0, to solve for percent ionization. Find the percent ionization of a 2.5 M HNO2 solution. The Ka of nitrous acid is 4.6 x 10-4. HNO2 ⇄ H+ + NO2- 𝑲 𝒂 = H + [ NO 𝟐 − ] [ HNO 𝟐 ] = 𝒙 𝟐 𝟐.𝟓 −𝒙 (x is small) 𝟒.𝟔× 𝟏𝟎 −𝟒 = 𝒙 𝟐 𝟐.𝟓 Solve for x, which equals [H+]
67
Acid-base properties of salts
Salts are ionic compounds (cation + anion) When dissolved in water, some salts are pH-neutral, some are acidic, and some are basic IN GENERAL, anions tend to form basic or neutral solutions. IN GENERAL, cations tend to form acidic or neutral solutions.
68
Anions as weak bases Anions can be thought as the conjugate base of an acid (the acid lost its proton, H+) This anion is the conjugate base of this acid Cl- HCl F- HF NO3- HNO3 C2H3O2- HC2H3O2
69
Anions as weak bases This anion is the conjugate base of this acid Cl- HCl F- HF NO3- HNO3 C2H3O2- HC2H3O2 In general, the anion A- is the conjugate base of HA. However, not every anion will act as a base… Conjugate base of a weak acid, it’s a weak base Conjugate base of a strong acid, it’s pH-neutral
70
Classify the anion as basic or pH-neutral:
NO3- NO2- C2H3O2- Conj. Base of a strong acid ∴ pH-neutral Conj. Base of a weak acid (HNO3) ∴ weak base Conj. Base of a weak acid (HC2H3O2) ∴ weak base
71
Cations as weak acids Cations that are the counterions of strong bases
NaOH, KOH, and Ca(OH)2 are examples of strong bases, and form OH- in solution. Cations Na+, K+, and Ca2+ do not contribute to acidity THEREFORE, they are pH-neutral
72
Cations that are the conjugate acids of weak bases
A cation can be formed from any non-ionic weak base by adding a proton, H+. Cations can be thought as the conjugate acid of an base (the base gained a proton, H+) This cation is the conjugate acid of this weak base NH4+ NH3 C2H5NH3+ C2H5NH2 CH3NH3+ CH3NH2
73
BH+(aq) + H2O(aq) ⇄ H3O+(aq) + B(aq)
This cation is the conjugate acid of this weak base NH4+ NH3 C2H5NH3+ C2H5NH2 CH3NH3+ CH3NH2 Cations with the general formula BH+ will act as a weak acid according to the equation: BH+(aq) + H2O(aq) ⇄ H3O+(aq) + B(aq) Conjugate acid of a weak base, it’s a weak acid
74
Classify the cation as acidic or pH-neutral:
C5H5NH+ Ca2+ Cr3+ Conj. Acid of a weak base ∴ a weak acid Conj. Acid of a strong base ∴ pH-neutral Small, highly charged cation ∴ a weak acid
76
Strong Acid – Strong base
Reacts completely Yields neutral solution (pH = 7) Example: HCl + NaOH H2O(l) + NaCl Net ionic equation: H+(aq) + OH-(aq) H2O(l)
77
Strong Acid – Weak base Reacts completely
Yields a weak acid (pH < 7) Weak acid is a product of the reaction (it’s the conj. acid of the strong base) Example: HCl + CH3COONa(aq) CH3COOH(aq) + NaCl(aq) Net Ionic Equation: H+(aq) + CH3COO-(aq) CH3COOH
78
CH3COOH(aq) + OH-(aq) CH3COO-(aq) + H2O(l)
Weak acid – strong base Reacts completely Yields a weak base (pH > 7) Weak base is a product of the reaction (it’s the conj. base of the strong acid) Example: CH3COOH(aq) + NaOH(aq) Net Ionic Equation: CH3COOH(aq) + OH-(aq) CH3COO-(aq) + H2O(l)
79
Weak acid – Weak base Does not react well
Yields a buffer solution (described later) Both a weak acid & weak base exist together Example: CH3COOH(aq) + CH3COO-(aq) CH3COOH(aq) + CH3COO-(aq) No net reaction
80
L acid 1 L X mol acid (H+) 1 mol acid (H+) 1 mol base (OH-) Y mol base (OH-) L base 1 L Y mol base (OH-) 1 mol base (OH-) 1 mol acid (H+) X mol acid (H+)
81
Equilibrium lies to the side of the weaker acid and base
82
Acids Donate ONE proton at a time!
monoprotic--acids donating one H+ (ex. HC2H3O2) diprotic--acids donating two H+'s (ex. H2C2O4) polyprotic--acids donating many H+'s (ex. H3PO4) polyprotic bases--accept more than one H+; anions with −2 and −3 charges (ex. PO43− ; HPO42−) Amphiprotic or amphoteric --molecules or ions that can behave as EITHER acids or bases; water, anions of weak acids (look at the examples above—sometimes water was an acid, sometimes it acted as a base)
83
Autoionization of water (Video)
Add notes to page 7 using the video link above. Include examples given in the video.
84
Autoionization of water
H2O(l) ⇄ H+(aq) + OH-(aq) 2 H2O ⇄ OH- + H3O+ See video for notes
85
H+/OH- Equilibrium See video for notes Kw =
86
What is the ion-product constant? How does it relate to [H+] and [OH-]?
See video for notes
87
Acidic or basic or neutral?
It is important to recognize the meaning of Kw. In an aqueous solution at 25°C, no matter what it contains, [H+] x [OH-] = 1.0 x There are three possible situations: A neutral solution, where [H+] = [OH-]. An acidic solution, where [H+] > [OH-]. A basic solution, where [H+] < [OH-].
88
Other temperatures… (add to p. 7)
If at a temperature OTHER THAN 25°C, the Kw will be a different value. Remember that the numerical value of Keq is dependent on temperature!
89
Example 1 𝑲 𝒘 = H + OH − =𝟏.𝟎× 𝟏𝟎 −𝟏𝟒 (since it’s at 25°C)
Calculate [H+] or [OH-] as required for each of the following solutions at 25°C, and state whether the solution is neutral, acidic, or basic. 1.0 x 10-5 M OH- 1.0 x 10-7 M OH- 𝟏.𝟎× 𝟏𝟎 −𝟏𝟒 = H + (𝟏.𝟎× 𝟏𝟎 −𝟓 ) [OH-] > [H+] ∴ basic H + = 𝟏.𝟎× 𝟏𝟎 −𝟏𝟒 𝟏.𝟎× 𝟏𝟎 −𝟓 = 𝟏.𝟎× 𝟏𝟎 −𝟗 [OH-] = [H+] ∴ neutral 𝟏.𝟎× 𝟏𝟎 −𝟏𝟒 = H + (𝟏.𝟎× 𝟏𝟎 −𝟕 ) H + = 𝟏.𝟎× 𝟏𝟎 −𝟏𝟒 𝟏.𝟎× 𝟏𝟎 −𝟕 = 𝟏.𝟎× 𝟏𝟎 −𝟕
90
Example 1 𝑲 𝒘 = H + OH − =𝟏.𝟎× 𝟏𝟎 −𝟏𝟒 (since it’s at 25°C)
Calculate [H+] or [OH-] as required for each of the following solutions at 25°C, and state whether the solution is neutral, acidic, or basic. 10.0 M H+ 𝟏.𝟎× 𝟏𝟎 −𝟏𝟒 =(𝟏𝟎.𝟎) OH − [H+] > [OH-] ∴ acidic OH − = 𝟏.𝟎× 𝟏𝟎 −𝟏𝟒 𝟏𝟎.𝟎 = 𝟏.𝟎× 𝟏𝟎 −𝟏𝟓
91
Example 2 At 60°C, the value of Kw is 1 x 10-13.
Using Le Chatelier’s principle, predict whether the reaction is exothermic or endothermic 2 H2O ⇄ H3O+ + OH- At 25°C, Kw = 1 x 10-14 At a higher temperature, Kw = 1 x Kw increases with temperature, energy is a reactant, and so the process must be endothermic. (The greater the K, the more products you have.)
92
Example 2 At 60°C, the value of Kw is 1 x 10-13.
Calculate [H+] and [OH-] in a neutral solution at 60°C. 2 H2O ⇄ H3O+ + OH- 𝟏.𝟎× 𝟏𝟎 −𝟏𝟑 = H + O H − 𝟏.𝟎× 𝟏𝟎 −𝟏𝟑 = 𝒙 𝟐 𝟏.𝟎× 𝟏𝟎 −𝟏𝟑 = 𝒙 𝟐 𝟑× 𝟏𝟎 −𝟕 𝑴=𝒙= H + = O H −
93
At 10°C, the autoionization of water equals 2. 9 x 10-15
At 10°C, the autoionization of water equals 2.9 x Calculate [H+] and [OH-] as necessary under each of the following conditions: Calculate [H+] if [OH-] = 9.3 x 10-4 M. Is the solution acidic or basic? Calculate [H+] and [OH-] for a neutral solution. Calculate [OH-] if [H+] = 6.7 x M. Is the solution acidic or basic?
94
pH Scale https://www.youtube.com/watch?v=pFK16GsU1e4
Add notes to page 9 using the video link above. Include examples given in the video.
95
pH Scale See video for notes 7 14
96
Why does [H+] = [OH-] at pH 7?
See video for notes
97
pH and pOH See video for notes pH [H+] (M) [OH-] (M) pOH 7 6 3 12
98
pH and pOH What is the pattern between pH and [H+]?
What is the relationship between [H+] and [OH-]? How is pH related to pOH?
99
Calculating pH https://www.youtube.com/watch?v=aw-Y1d2IIJc
Add notes to page 10 using the video link above. Include examples given in the video.
100
See video for notes pH = – log[H+] pOH = – log[OH–]
The pH of a solution is 3.75, what is the Hydrogen ion concentration, [H+]?
101
Examples What is the pH of a solution with a hydrogen ion concentration of 2.0 x 10-11? Calculate the pH of a 1.0 x 10-3 M OH- solution. (Hint: Use Kw to first find [H+]. Assume 25°C.) What is the pOH of a solution with a hydroxide ion concentration of 1.8 x 10-4? Calculate the pOH of a 1.0 M H+ solution. (Hint: Use Kw to first find [OH-]. Assume 25°C.) The pH of human blood was measured to be 7.41 at 25°C. Calculate the pOH, [H+], and [OH-] for the sample. 10.70 11.00 3.74 14.00 pOH = 6.59, [H+] = 3.9 x 10-8 M, [OH-] = 2.6 x 10-7 M
Similar presentations
© 2025 SlidePlayer.com Inc.
All rights reserved.