Thinking Like a Chemist About Acids and Bases Part V UNIT 6 DAY 10

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Thinking Like a Chemist About Acids and Bases Part V UNIT 6 DAY 10 What are we going to learn today? Explore Acid – Base Titrations Explore the concept of protonation and pKa Explore Behavior of Polyprotic Acids Acid Base Titration Why do a titration? You have a solution with an unknown property Unknown Concentration? Unknown Ka (Kb)? Both Slowly neutralize the solution by adding a strong base (acid) monitor the pH with each addition What do these plots tell you? How is the plot on the right different? Work with neighbors on Titration Discovery Activity Poll: Clicker Question The initial concentration of the HBr is: A) 7 M B) 0.7 M C) 0.007 M D) 0.0007 M E) 3.5 M Poll: Clicker Question The pKa for acetic acid is: A) 1.7 x 10-5 B) 1.6 x 10-9 C) 4.76 D) 8.32 E) 3.43 Chemical Equilibrium pH indicator Chemical Equilibrium pH indicator Bromothymol Blue, pKa = 7.1 Protonated form Deprotonated form yellow blue Poll: Clicker Question Chemical Equilibrium pH indicator Bromothymol Blue Bromophenol Blue has a pKa of around 7. When it is protonated (HA form) it is yellow, when it is deprotonated (A- form) it is blue. What color would in be in a solution in which the pH was 9? A. blue B. yellow C. green CH302 Vanden Bout/LaBrake Spring 2012 Polyprotic Acid Poll: Clicker Question Polyprotic Acid -4 Ka1 = 7.4 x 10 -5 Ka2 = 1.7 x 10 -7 Ka3 = 4.0 x 10 At pH = 2 how many of the acidic protons will be on the molecule? A. 0 B. 1 C. 2 D. 3 Poll: Clicker Question Polyprotic Acid -4 Ka1 = 7.4 x 10 -5 Ka2 = 1.7 x 10 -7 Ka3 = 4.0 x 10 At pH = 12 how many of the acidic protons will be on the molecule? A. 0 B. 1 C. 2 D. 3 CH302 Vanden Bout/LaBrake Spring 2012 If I add 0.1 mol NaOH to 0.05 mol H3PO4 what will be the dominant species in solution? -3 H3PO4 values: pKa1 = 7.5 x 10 pKa2 = 6.2 x 10-8 pKa3 = 4.8 x 10-13 - A. H3PO4 and H2PO4 - B. H2PO4 - 2- C. H2PO4 and HPO4 2- D. HPO4 2- 3- E. HPO4 and PO4 What did we learn today? Acid Base titrations are performed to determine the concentration of an acid or base and/or the Ka of an acid or Kb of a base. The pH can be calculated by determining the ending concentrations after a series of neutralization reactions are performed. pKa indicates the extent of ionization of an acid Lower the pKa value, the more acidic an environment necessary to keep the acid protonated IMPORTANT INFORMATION HW07 Exam 2 – Tuesday, March 4th - Rooms TBA .

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Bromothymol Blue
Safety Data Sheet Bromothymol Blue 1. PRODUCT AND COMPANY IDENTIFICATION Product Name: Bromothymol Blue Synonyms/Generic Names: 4,4'-(3H-2,1-Benzoxathiol-3-ylidene)bis[2-bromo-3-methyl-6-(1- methylethyl)phenol]S,S-dioxide sodium salt SDS Number: 116.00 Product Use: For Educational Use Only Manufacturer: Columbus Chemical Industries, Inc. N4335 Temkin Rd. Columbus, WI. 53925 For More Information Contact: Ward's Science 5100 West Henrietta Rd. PO Box 92912-9012 Rochester, NY 14692 (800) 962-2660 (Monday-Friday 7:30-7:00 Eastern Time) In Case of Emergency Call: CHEMTREC - 800-424-9300 or 703-527-3887 (24 Hours/Day, 7 Days/Week) 2. HAZARDS IDENTIFICATION OSHA Hazards: No known OSHA hazards. Target Organs: None Signal Word: Warning Pictograms: None GHS Classification: Acute toxicity, Oral Category 5 GHS Label Elements, including precautionary statements: Hazard Statements: H303 May be harmful if swallowed. Precautionary Statements: P312 Call a POISON CENTER or doctor/physician if you feel unwell. Potential Health Effects Eyes May cause eye irritation. Inhalation May be harmful if inhaled. Causes respiratory tract irritation. Skin May be harmful if absorbed through skin. Causes skin irritation. Ingestion May be harmful if swallowed. Revised on 01/07/2013 Page 1 of 5 NFPA Ratings HMIS Ratings Health 1 Health 1 Flammability 1 Fire 1 Reactivity 0 Reactivity 0 Specific hazard Not Available Personal E 3. COMPOSITION/INFORMATION ON INGREDIENTS EINECS# / Molecular Component Weight % CAS # Formula ELINCS# Weight Bromothymol Blue 100 34722-90-2 N/A C27H27Br2NaO5S 646.36 g/mol 4. FIRST-AID MEASURES Eyes Rinse with plenty of water for at least 15 minutes and seek medical attention if necessary.
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(12) United States Patent (10) Patent No.: US 8,062,902 B2 Mestrallet (45) Date of Patent: Nov
US008062902B2 (12) United States Patent (10) Patent No.: US 8,062,902 B2 Mestrallet (45) Date of Patent: Nov. 22, 2011 (54) MAMMALLAN DISEASE DETECTION (56) References Cited SYSTEM U.S. PATENT DOCUMENTS (75) Inventor: Francois Mestrallet, Longvie (FR) 3,978,818. A * 9, 1976 Heldenbrand ................ 119, 170 5,005,572 A * 4, 1991 Raemer et al. ... 128.207.14 (73) Assignee: Nullodor USA LLC 5,143,023 A * 9/1992 Kuhns ........................... 119,173 5,267,532 A * 12/1993 Franklin et al. ... ... 119,173 (*) Notice: Subject to any disclaimer, the term of this 5,279,259 A * 1/1994 Rice et al. ...... ... 119,173 patent is extended or adjusted under 35 5.362,633 A * 1 1/1994 Pugia .............................. 435/28 U.S.C. 154(b) by 129 days. 5,371,054 A * 12/1994 Pluta et al. ...................... 5O2.62 5,830,765 A * 1 1/1998 Santioemmo et al. .......... 436.66 (21) Appl. No.: 12/394,220 5,970,915 A * 10/1999 Schlueter et al. ...... ... 119,171 6,382,132 B1* 5/2002 Steckel et al. ..... ... 119,171 (22) Filed: Feb. 27, 2009 7,485.466 B2 * 2/2009 Jenkins et al. .................. 436.86 7,670,845 B2* 3/2010 Wenzel et al. ... ... 436,163 (65) Prior Publication Data 2004/OO25798 A1* 2, 2004 Lee et al. .... 119,172 2005/014518.6 A1* 7/2005 Fung et al. 119,171 US 2009/03253O4 A1 Dec. 31, 2009 2006/0270.051 A1* 11/2006 Jenkins et al. .................. 436.86 Related U.S. Application Data * cited by examiner (60) Provisional application No.
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Bromothymol Blue MSDS # 116.00
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3 1 0 Material Safety Data Sheet
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UNIT6-DAY7-Lab1230pm Wednesday, February 27, 2013 5:34 PM
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