pH Scale Soren Sorensen (1868 - 1939) pH Scale Acid Base 0 7 14 Zumdahl, Zumdahl, DeCoste, World of Chemistry  2002, page 515 [H + ] pH 10 -14 14 10.

Slides:



Advertisements
Similar presentations
PH and pOH Chem 332 – ODette. pH (Potential of Hydrogen) Measures the degree of acidity or basicity of an aqueous solution Corresponds to the hydrogen.
Advertisements

pH Scale and Calculations Chapter 14 Page
pH Scale and Calculations Chapter 14 pH Scale We use this scale to measure the strength of an acid or base. pH is defined as the –log[H+] pH can use.
PH of Common Substances Timberlake, Chemistry 7 th Edition, page 335.
pH Scale Soren Sorensen ( ) pH Scale Acid Base Zumdahl, Zumdahl, DeCoste, World of Chemistry  2002, page 515 [H + ] pH
pH Scale In this presentation you will:
Copyright © 2005, N. Ahbel Understanding pH Sources: 1. Anthony Carpi, Acids, Bases and pH,
Acids and Bases 1.
Self Ionisation of Water Water undergoes Self Ionisation H 2 O (l) ⇄ H + (aq) +OH - (aq) or H 2 O (l) + H 2 O (l) ⇄ H 3 O + (aq) +OH - (aq) The concentration.
Self Ionisation of Water Water undergoes Self Ionisation H 2 O (l) ⇄ H + (aq) +OH - (aq) or H 2 O (l) + H 2 O (l) ⇄ H 3 O + (aq) +OH - (aq) The concentration.
Acids, Bases, & Salts What is an ACID? pH less than 7.
pH less than 7 Neutralizes bases(form salts and water) Forms H + (H 3 O + ) ions in solution Corrosive-reacts with most metals Good conductors of electricity.
1. Take out HW and Stamp Sheet  #’s 20-22,24,32a,34a,35,36  #’s 31a,33a,37,39,40, 48-50,56,58ab 2. Solve this problem: What is the pH of a solution with.
Acids and Bases pH and pOH.
PH.
More break down = stronger acid
LecturePLUS Timberlake1 Acids and Bases. LecturePLUS Timberlake2 Acids and Bases Acids produce Hydrogen (H +) in solutions Bases produce Hydroxide (OH.
The pH Scale. pH Scale We use this scale to measure the strength of an acid or base. pH is defined as the –log[H+] pH can use the concentration of hydronium.
Review Acids & Bases. Naming Acids & Bases Remember: H & an element = hydro__ic acid -ate polyatomic = ___ic acid -ite polyatomic = ___ous acid.
Acid-Base chemistry Acidity of blood (pH range of Heartburn (acid-reflux) – Tums, Rolaids, Milk of Magnesia; The Purple Pill , Nexium Acidity regulation.
Chemistry Chapter 19 Practice with acids and bases.
The pH Scale.
The pH Scale. [H + ]pHExample Acids 1 X HCl 1 x Stomach acid 1 x Lemon juice 1 x Vinegar 1 x Soda 1 x Rainwater.
In aqueous solution… In aqueous solution… HCl (aq)  H + (aq) + Cl - (aq) Acids Acids increase hydrogen ion concentration [H + ] Courtesy Christy Johannesson.
Figure Water is Central to Life Water has several properties that life is dependent upon including: Cohesion High heat of vaporization High specific.
Acids and Bases Special kinds of aqueous solutions “Ionization”
Ch. 16 Notes -- Acids and Bases What makes something an acid? Acid Properties: (1) tastes _______-- _______________ (2) corrosive to _________ (3) contains.
Unit 3 Acids and Bases. Hydrogen ions and pH Ion product constant of water (K w ) H 2 O  H + + OH - In pure water : [H + ] = [OH - ] * [ ] are used to.
Let’s take a look at water  2H 2 O  H 3 O + + OH -  [H 3 O + ][OH - ]= 1x M 2  [H 3 O + ]= 1x10 -7 M  [OH - ]= 1x10 -7 M  K w = 1x M.
Ch. 20 Notes -- Acids and Bases What makes something an acid? Acid Properties: (1) tastes _______-- _______________ (2) corrosive to _________ (3) contains.
Acids and Bases.
Learning Check pH2 The [OH-] of a solution is 5 x M. What is the [H 3 O + ] of the solution? 1) 2 x M 2) 1 x M 3) 2 x M.
pH Scale Soren Sorensen ( )
Acids & Bases pH. Ionization of Water H 2 O + H 2 O H 3 O + + OH - K w = [H 3 O + ][OH - ] = 1.0  Kw=ionization constant for H2O.
Fig Fig. 3-2 Hydrogen bond  – – H  + + H O — —  + +  + +  + +  – –  – –  – –
Acids & Bases.
Chapter 20 pH. Water forms ions H 2 O ----> H + + OH - Water splits apart into hydrogen ions (H+) and hydroxide ions (OH-). This process is called self-ionization.
Dec 8, 2010 BellRinger Finish the rest of your interviews, you have 15 min! Objectives Practice presenting research projects in an a style similar to the.
PROPERTIES OF: ACIDS Taste sour Blue litmus turns red Reacts with metals to make H 2 gas. Contains a H at the start of the formula(HCl, H 2 SO 4 ) BASES.
CHAPTER 16 – ACIDS AND BASES ACID – A compound the produces hydrogen ions in a water solution HCl (g) → H + (aq) + Cl - (aq) BASE – A compound that produces.
Acids and Bases ACIDS and BASES
LECTURE PRESENTATIONS For CAMPBELL BIOLOGY, NINTH EDITION Jane B. Reece, Lisa A. Urry, Michael L. Cain, Steven A. Wasserman, Peter V. Minorsky, Robert.
Oceanography Chapter 7 WATER QUALITY “What You Need To Know To Keep Your Fish Alive” Adapted from Gary Fornshell, University of IdahoTerry Patterson,
PH.
Understanding pH Sources:
Acids and Bases--pH.
The pH Scale Hydronium & Hydroxide Ions (H3O+) (OH–) pH Scale
Ch. 16 Notes -- Acids and Bases
Water Chemistry and Acid/Base Review
DO NOW... HINT...if log (x) = y, then x = 10y PH, pOH & logs!
pH Scale Soren Sorensen ( )
HCl(aq)  H+(aq)+ Cl-(aq)
Goals to Accomplish Today
The pH scale and what does it mean?
Review Practice What is the molality of a solution created by adding 58 grams of magnesium hydroxide to 4 liters of water? Answer: 0.25 m Mg(OH)2 What.
The pH Scale Hydronium & Hydroxide Ions (H3O+) (OH–) pH Scale
Unit 14 – Acid, Bases, & Salts
Unit 13 – Acid, Bases, & Salts
Acids and bases BrainPop.
Self Ionisation of Water
Acids and Bases.
Unit 13 – Acid, Bases, & Salts
PH and pOH Chem 332.
PH and pOH Chem 332 – O’Dette.
Unit 15 – Acid, Bases, & Salts
Unit 13 – Acid, Bases, & Salts
Unit 14 – Acid, Bases, & Salts
Unit 13 – Acid, Bases, & Salts
DO NOW... HINT...if log (x) = y, then x = 10y
Self Ionisation of Water
Presentation transcript:

pH Scale Soren Sorensen ( )

pH Scale Acid Base Zumdahl, Zumdahl, DeCoste, World of Chemistry  2002, page 515 [H + ] pH M NaOH Ammonia (household cleaner) Blood Pure wate Milk Vinegar Lemon juice Stomach acid 1 M HCl Acidic Neutral Basic

pH of Common Substances Timberlake, Chemistry 7 th Edition, page 335

pH of Common Substance 14 1 x x x x x x x x x x x x x x x x x x x x x x x x x x x x NaOH, 0.1 M Household bleach Household ammonia Lime water Milk of magnesia Borax Baking soda Egg white, seawater Human blood, tears Milk Saliva Rain Black coffee Banana Tomatoes Wine Cola, vinegar Lemon juice Gastric juice More basic More acidic pH [H 1+ ] [OH 1- ] pOH 7 1 x x

Acid – Base Concentrations pH = 3 pH = 7 pH = 11 OH - H3O+H3O+ H3O+H3O+ H3O+H3O+ [H 3 O + ] = [OH - ] [H 3 O + ] > [OH - ] [H 3 O + ] < [OH - ] acidic solution neutral solution basic solution concentration (moles/L) Timberlake, Chemistry 7 th Edition, page 332

pH pH = -log [H 1+ ] Kelter, Carr, Scott, Chemistry A World of Choices 1999, page 285

pH Calculations pH pOH [H 3 O + ] [OH - ] pH + pOH = 14 pH = -log[H 3 O + ] [H 3 O + ] = 10 -pH pOH = -log[OH - ] [OH - ] = 10 -pOH [H 3 O + ] [OH - ] = 1 x10 -14

pH = - log [H + ] pH = 4.6 pH = - log [H + ] 4.6 = - log [H+] = log [H+] Given: 2 nd log 10 x antilog multiply both sides by -1 substitute pH value in equation take antilog of both sides determine the [hydronium ion] choose proper equation [H + ] = 2.51x10 -5 M You can check your answer by working backwards. pH = - log [H + ] pH = - log [2.51x10 -5 M] pH = 4.6 Recall, [H + ] = [H 3 O + ]

7dFields-Jeff/AcidBase1.htm pH and pOH Calculations

Acid Dissociation monoprotic diprotic polyprotic HA(aq) H 1+ (aq) + A 1- (aq) 0.3 M pH = - log [H + ] pH = - log [3M] pH = e.g. HCl, HNO 3 H 2 A(aq) 2 H 1+ (aq) + A 2- (aq) 0.3 M0.6 M0.3 M pH = - log [H + ] pH = - log [6M] pH = e.g. H 2 SO 4 Given: pH = 2.1 find [H 3 PO 4 ] assume 100% dissociation e.g. H 3 PO 4 H 3 PO 4 (aq) 3 H 1+ (aq) + PO 4 3- (aq) ? Mx M pH = ?

Given: pH = 2.1 find [H 3 PO 4 ] assume 100% dissociation H 3 PO 4 (aq) 3 H 1+ (aq) + PO 4 3- (aq) X MX M M Step 1) Write the dissociation of phosphoric acid Step 2) Calculate the [H + ] concentration pH = - log [H + ] 2.1 = - log [H + ] = log [H + ] 2 nd log = log [H + ] 2 nd log [H + ] = 10 -pH [H + ] = [H + ] = M [H + ] = 7.94 x10 -3 M 7.94 x10 -3 M Step 3) Calculate [H 3 PO 4 ] concentration Note: coefficients (1:3) for (H 3 PO 4 : H + ) 7.94 x10 -3 M 3 = M H 3 PO 4

How many grams of magnesium hydroxide are needed to add to 500 mL of H 2 O to yield a pH of 10.0? Step 1) Write out the dissociation of magnesium hydroxide Mg 2+ OH 1- Mg(OH) 2 Mg(OH) 2 (aq)Mg 2+ (aq) 2 OH 1- (aq)+ Step 2) Calculate the pOH pH + pOH = pOH = 14 pOH = 4.0 Step 3) Calculate the [OH 1- ] pOH = - log [OH 1- ] [OH 1- ] = 10 -OH [OH 1- ] = 1 x10 -4 M 1 x10 -4 M0.5 x10 -4 M5 x10 -5 M Step 4) Solve for moles of Mg(OH) 2 x = 2.5 x mol Mg(OH) 2 Step 5) Solve for grams of Mg(OH) 2

7dFields-Jeff/AcidBase1.htm Practice Problems - Key Practice Problems - Answer Key