61. Acids Bases Salts acids, bases, and Salts. This page leads you to different areas of interest. http://www.sciencebyjones.com/acids_bases_salts.htm

Acids, Bases, and Salts This page leads you to different areas of interest. Acids Definitions pH math Bases ... Quiz Acids In everyday life we deal with many compounds that chemists classify as acids. For example, orange juice and grapefruit juice contain citric acid. These juices, and others, also contain ascorbic acid, a substance more commonly known as Vitamin C. Salads are often flavored with vinegar, which contains dilute acetic acid. Boric acid is a substance that is sometimes used to wash the eyes. In any chemistry laboratory, we find acids such as hydrochloric acid, sulfuric acid, and nitric acid. These acids are called mineral acids because they can be prepared from naturally occurring compounds called minerals. Mineral acids are generally stronger than household acids, and should be handled with great care because they can burn skin and clothing. Properties of Acids: Acids taste sour . Citric acid is responsible for the sour taste of lemons, limes, grapefruits, and oranges. Acetic acid is responsible for the sour taste of vinegar. Acids turn litmus (or indicator papers) red.

62. Acids And Bases acids and bases. Despite its shortcomings the theory is widely used to calculateequilibrium data for weak electrolytes, including acids and bases, in water. http://www.tannerm.com/acidbase.htm

Acids and bases The Arrhenius dissociation model The Arrhenius theory defines acids and bases as isolated species in solution giving rise respectively to hydrogen ions H and hydroxyl ions OH . Interaction with solvents is ignored. The theory cannot begin to explain acidic and alkaline properties in non-aqueous solvents. Despite its shortcomings the theory is widely used to calculate equilibrium data for weak electrolytes, including acids and bases, in water. For a generalized binary weak electrolyte MX (e.g., HCl) at concentration C, a fraction a ionizes. There will be an equilibrium mixture of (1-a)C of MX and aC of both M and X . The equilibrium for the dissociation process MX = M + X is given by K = ( [M ] [X ] ) / [MX] = a C / (1- a If a a C. This is called the Ostwald Dilution Law. The Bronsted-Lowry concept of acids and bases Acids are defined as proton donors and bases as proton acceptors regardless of whether the species are are ionic or neutral. In general acid = base + proton Specific examples are H SO = HSO + H HSO = SO + H H O = H O + H OH = O + H The species on the right, along with the proton is known as the conjugate base. Conjugate acids are defined in a similar way. In aqueous solution the concept includes solvent interaction.

63. Identifying Acids And Bases Identifying acidbase species. Being able to readily identify a specieswith regards to a acid/base behavior is a very useful skill. http://www.psigate.ac.uk/newsite/reference/chemlecs/acidorbase.html

64. Chemical Sciences Ionization Constants Of Acids And Bases acids and bases Ionization Constants of acids and bases. The ionization constantsof acids and bases other than water are dealt with in a similar way. http://www.psigate.ac.uk/newsite/reference/plambeck/chem1/p01133.htm

65. Learn.co.za : Chemistry Characteristics of acids and bases. Note Solutions indicators. acidsand bases react to neutralise each other. Points to remember ! http://www.learn.co.za/content/grade12/Science/chem_acidsbases/bass/Unit1/

You are here: Classroom Grade 12 Science Chemistry : Acids and Bases ... Acids and Bases : 1. Characteristics of Acids and Bases Other units in this lesson: 2. Acid/Base models 3. Conjugate Acid/Base pairs 4. Acid/Base terminology 5. pH scale and calculations ... 9. Hydrolysis Characteristics of acids and bases Note: Solutions of acids and bases cause a colour change of indicators. Acids and bases react to neutralise each other. Points to remember ! Solutions of acids or bases conduct electricity due to the presence of free ions. Acids taste sour and are clear. Bases feel soapy and are cloudy. Other units in this lesson: 2. Acid/Base models 3. Conjugate Acid/Base pairs 4. Acid/Base terminology 5. pH scale and calculations ... 9. Hydrolysis

66. Acids And Bases http://www.harcourtschool.com/activity/acids/

67. Chem - Topic 9 - Acids And Bases Topic 9 acids and bases. 9.1 Properties of acids and bases. Examples ofbases NaOH, NH 3 , CH 3 COO - . 9.2 Bronsted-Lowry acids and bases. http://homepage.mac.com/stray/ib/chem/SSC/topic9.html

Topic 9 - Acids and Bases 9.1 Properties of acids and bases 9.1.1 : Properties of acids and bases in aqueous solutions on stuff...nb...the term alkali refers to a base dissolved in water. Indicators...they change color depending on whether they're in acidic or basic conditions...each one's different, so I suppose I'd better list some common ones... Methyl orange Bromophenol blue Methyl red Bromothymol blue Phenolphtalein Acid red yellow red yellow colorless Base yellow blue yellow blue red Each one change color as a different pH, and so there will be cases where one is useful and others are not. (not really necessary is SL?) O + NaCl. + H Acids with carbonates...will produce water and CO ie 2HCl + CaCO + H O + CaCl 9.1.2 : Experimental properties of acids and bases...when acids and bases neutralize, the reaction is noticeably exothermic (ie heat can be felt coming from the reaction). Obviously, they will have an effect on the color of indicators as described above. The hydrogen produced in the reaction of acids with metal will produce a 'pop' sound if a match is held to it, and the CO from the carbonate reaction will turn limewater a milky white when bubbled trough it.

68. Laboratory - PH Of Acids And Bases :pKa And PKb Values Here you can select the acids and bases on their pKa values. There s also ashort explanation about pH calculations. acids and bases pKa and pKb. http://home.planet.nl/~skok/techniques/laboratory/pka_pkb.html

Acids and Bases: pKa and pKb What's on this page? Click here for theory about pH Browse direct to the Table of pKa values for acids or Table of pKb values for bases . (Legend at the bottom of this page). A list of commonly used HPLC-buffers with their working range and UV cutoff as well as other links to buffer-sites can be found elsewhere on the Laboratory-pages. pH theory The relationship between pH, pKa, and the relative concentrations of an acid and its salt is as follows: [A ] the molar concentration of the salt (dissociated species) [HA] the concentration of the undissociated acid When the concentrations of the salt and acid are equal, the pH of the system equals the pKa of the acid. The percentage ionisation from a given pKa value can be calculated at Reall pKa and pKb tables Make your choice: Table of pKa values for acids or Table of pKb values for bases . Click here for the abbreviations used in the tables. You can always return to this index by mouse-double click. Acids T(°C) pKa Acetic acid ACES ADA Benzoic acid Bicine BIS-TRIS Propane o-Boric acid (1) o-Boric acid (2) o-Boric acid (3) Carbonic acid (1) Carbonic acid (2) CAPS CHES Citrate (1) Citrate (2) Citrate (3) Acids T(°C) pKa Diethylmalonic acid Formic acid Glycylglycine HEPES HEPPS Imidazole MES MOPS PIPES

69. The Basics Of Acids And Bases The Basics of acids and bases acids and bases play a key role in the chemistry thataffects your daily life. Many manufacturing processes use acids and bases. http://www.scs.k12.tn.us/STT99_WQ/STT99/Bolton_HS/tippette/WEBQUEST/WQUEST.HTM

The Basics of Acids and Bases a WebQuest for high school chemistry by Eric Tippett Introduction Task Resources Process ... Conclusion Introduction The Task In this WebQuest assignment, you will : describe and compare the properties of acids and bases describe and compare three models of acids and bases (Bronsted-Lowry, Lewis, Arrhenius) distinguish between strong and weak acids and bases classify common substances as acidic or basic discuss the potential problem of acid rain. Resources In addition to your chemistry text, the following websites will be available to you: Acid and Base pH Tutorial Chem 4 Kids Acids and Bases Chemtutor Acids and Bases CHEMystery Acids and Bases ... SWOOPE Acid Rain Project All of these sites have good information that can help you in this project, and many of them have links to other useful sites that are related to acids and bases. The Process To do this project, you will first need to assemble into groups of 3. This project can basically (ha-ha) be broken down into 4 assignments: Assignment 1 In this assignment, your group will construct a visual poster presentation that compares the properties of acids and bases. In addition, you will construct a visual presentation that compares three models of acids and bases: Arrhenius, Bronsted -Lowry, and Lewis. You should be extremely thorough and as detailed as possible. Be as creative as you can, gathering materials from the Internet and outside journal sources . Be prepared to present your findings to the rest of the class. As a group, you may divide up the assignment responsibilities as you decide. Also

70. Acids And Bases Quiz 2 - PH, Litmus pH, Litmus Grade 6 quiz - Covers pH, Boyle s law, litmus color changesfor acids and bases, etc 1001 acids and bases Quiz 2. http://www.1001-periodic-table-quiz-questions.com/quiz/k-12/acids_and_bases_2.ht

1001-periodic-table-quiz-questions.com Home About Us Periodic Table Reference Chemistry Links ... Tell a Friend Related Sites Mercury Venus Earth Mars ... Pluto Other Links Galileo Galilei Moon Phases Why is the sky blue Periodic table quizes ... Prince by machiavelli Sponsors Telescopes.com Binoculars.com Peepers.com Acids and Bases Quiz 2 Home Grade 6 Quizzes 1) The pH of a neutral solution is 6.99 True False 2) Pick the true statement: Basic solutions have a pH of less than 7 Basic solutions have a pH of more than 7 3) The pH of acid solutions is more than the pH of basic solutions. True False 4) Pick the false statement: Acids change litmus from red to blue Acids change litmus from blue to red 5) Pick the true statement: A pH of less than 7 means acidic, more than 7 means basic. A pH of less than 7 means basic, more than 7 means acidic. 6) Pick the true statement about pH below: pH stands for the power of H pH stands for the power of p pH stands for the power of pH pH stands for the power of Hp 7) ...... change litmus from red to blue

71. Polyprotic, Arrhenius - Acids And Bases Quiz 4 - polyprotic, Arrhenius Grade 6 quiz - Covers polyprotic, Arrhenius, litmuscolor changes for acids and bases, etc acids and bases Quiz 4. http://www.1001-periodic-table-quiz-questions.com/quiz/k-12/acids_and_bases_4.ht

1001-periodic-table-quiz-questions.com Home About Us Periodic Table Reference Chemistry Links ... Tell a Friend Related Sites Mercury Venus Earth Mars ... Pluto Other Links Galileo Galilei Moon Phases Why is the sky blue Periodic table quizes ... Prince by machiavelli Sponsors Telescopes.com Binoculars.com Peepers.com Acids and Bases Quiz 4 Home Grade 6 Quizzes 1) ...... acids only partially dissociates in water. strong weak 2) A conjugate base is formed when a/n ...... ...... a hydrogen ion. acid, donates acid, gains base, gains 3) ...... corrode metal. acids bases 4) ...... means having two ionizable hydrogens available. polyprotic monoprotic diprotic 5) According to Arrhenius: An acid is any substance that, when dissolved in water: increases the concentration of hydronium ion decreases the concentration of hydronium ion 6) What is a negatively charged ion called? Cation Anion 7) Pick the correct ways of writing the Hydronium ion: H H H 8) Pick the true statement about the nature of acids and bases: acids mixed with bases makes stronger acids bases mixed with acids makes stronger bases acids and bases neutralize each other 9) True or false - Acids taste sour, bases taste bitter.

72. Acids And Bases 1. 2. 3. 4. 5, acids and bases. Introduction. The fact that acids and bases havedifferent strength is explained as a result of a different degree of dissociation. http://utenti.lycos.it/Pasquale_Petrilli/ionicequ/electrol.htm

Acids and bases Introduction The classification of substances as acids was at first suggested by their sour taste (Latin acidus = sour; acetum = vinegar). Alkalis (Arabic al kali = ashes of a plant) were taken as those substances that could reverse or neutralize the action of acids. It was also believed that oxygen is a necessary constituent of acids (Greek oxus = sour; gennae = I produce). After Davy, that in 1810 demonstrated that hydrochloric acid contained only hydrogen and chlorine, hydrogen was taken as an essential constituent of acids. According to Arrhenius theory , the proton (H ) is responsible for acidic properties while the hydroxyl ion (OH ) is responsible for basic (alkaline) properties. Acids are thought as compounds which dissociate giving a proton (and its counter ion) such as: HCl = H + Cl CH COOH = H + CH COO Bases are thought as compounds which dissociate giving an hydroxyl ion (and its counter ion) such as: NaOH = Na + OH The fact that acids and bases have different strength is explained as a result of a different degree of dissociation. Thus HCl which is a strong electrolyte (fully dissociated) is a strong acid and acetic acid (a weak electrolyte, i.e., partially dissociated) is a weak acid. However, The following considerations, led in 1923 to a more general concept of acids and bases (Lowry-Bronsted theory): There are many evidences indicating that proton does not exist free in aqueous solution but it is bound to water (hydrated). Normally this hydrated proton is indicated as H

73. Acids And Bases acids and bases. Weak acids and bases only partially dissociate to form some ionsand there is still some of the original acid or base present in solution. http://wwwchem.csustan.edu/chem3070/3070M07.HTM

Acids and Bases ACIDS donate protons to water to form hydronium ions taste sour turn cabbage juice red turn litmus paper red BASES donate hydroxyl groups accept protons taste bitter feel slimey turn cabbage juice yellow, green or blue depending upon the solution concentration turn litmus paper blue pH The concentration of hydrogen ions is measured on a logrithmic scale: pH = - log [H O Table 1 shows the correlation between hydrogen ion concentration and pH. A solution with a low pH is acidic, and a solution with a high pH is basic. Solutions at a pH of 7 are neutral. Recipe for Cabbage juice: fill a blender with pieces of red (purple) cabbage add water blend to smithereens filter cabbage juice using a coffee filter The juice can be used to make a rainbow of colors corresponding to various (approximate) pH values. Strong acids and bases completely dissociate to form ionic species. There is none of the original acid or base left in solution. Weak acids and bases only partially dissociate to form some ions and there is still some of the original acid or base present in solution. For example, a .1M solution of HCl has a pH of 1, because all of the HCl reacts with water to form H O ions. Therefore all the moles that were once HCl are now H

74. Bronsted-Lowry Acids And Bases next up previous Next Lewis acids and bases Up Some classifications of acidsPrevious Arrhenius acids and bases BronstedLowry acids and bases. http://www.nyu.edu/classes/tuckerman/honors.chem/lectures/lecture_21/node3.html

Next: Lewis acids and bases Up: Some classifications of acids Previous: Arrhenius acids and bases Bronsted-Lowry acids and bases The Bronsted-Lowry definition is named for Johannes Bronsted and Thomas Lowry, who independently proposed it in 1923. A Bronsted-Lowry (BL) acid is defined as any substance that can donate a hydrogen ion (proton) and a Bronsted-Lowry base is any substance that can accept a hydrogen ion (proton). Thus, according to the BL definition, acids and bases must come in what is called conjugate pairs . For example, consider acetic acid dissolved in water: Notice that we have written explicitly in these reactions. The reason is that acid/base dissociation occurs by a proton transfer reaction from an acid species to a specific water molecule. The transfer occurs through a hydrogen bond between the acid molecule and a solvating water molecule. Here, CH COOH is a BL acid because it can donate a proton, and CH COO its conjugate base because it can accept a proton. Note that and also form such a conjugate pair.

75. Acids And Bases acids and bases. Introduction and Definitions acids and bases are encounteredfrequently both in chemistry and in everyday living. http://www.elmhurst.edu/~chm/vchembook/180acidsbases.html

Acids and Bases Elmhurst College Acids Acid-Base Strength ... Virtual ChemBook Acids and Bases Introduction and Definitions: Acids and bases are encountered frequently both in chemistry and in everyday living. They have opposite properties and have the ability to cancel or neutralize each other. Acids and bases are carefully regulated in the body by the lungs, blood, and kidneys through equilibrium processes. What are acids and bases? Observational definitions: Acids: Bases: Taste sour. Taste bitter. Give sharp stinging pain in a cut or wound. Feels slippery Turn blue litmus paper red. Turn red litmus paper blue. Turn phenolphthalein colorless. Turn phenolphthalein pink. React with metals to produce hydrogen gas. React with carbonates or bicarbonates to produce carbon dioxide gas. See the graphic on the left as a base is wiped over the paper which already has the indicator phenolphthalein on it. The drawing changes to pink. What are Acids and Bases - on a molecular level?

76. Acids, Bases And Indicators acids and bases are two different types of chemicals that have interestingproperties. acids, bases and Indicators. acids and bases http://www.kidscastle.si.edu/channels/science/articles/sciencearticle3.html

Acids, Bases and Indicators Acids and bases are two different types of chemicals that have interesting properties. You can do experiments with some of the common acids and bases, and you can even use some of these experiments in a magic show. Many acids and bases are corrosive; that is, they can dissolve or eat away substances by chemical action. For example, you can often see what looks like a white fungus around the wires of a car battery. This is corrosion caused by the extremely strong acid inside the battery. So you will have to be careful to use only the weak acids and bases described in these experiments. For your experiments you will need an indicator, a chemical that changes color when it is mixed with certain other chemicals such as acids and bases. Ordinary tea is a good indicator. Make a cup of very dark tea, then squeeze fresh lemon juice into the tea as you stir it. Notice that the tea becomes lighter and lighter in color. This is caused by adding an acid. In this case it is citric acid, which causes the sour taste in the lemon. Red cabbage is another very good indicator. You will also need several glasses, white vinegar (a weak acid), limewater (a weak base you can buy at the drugstore), a straw, and a pot for boiling some red cabbage leaves.

77. Chem1 Acids And Bases Chem1 acids and bases. If you teach base reactions; Recognizing commonacids and bases; Reactions of acids and bases; salts; The pH scale; Acid http://www.chem1.com/lessondesc/CB14.html

78. Dissociation Constants Of Organic Acids And Bases Dissociation Constants Of Organic acids And bases, This table liststhe acidbase dissociation constants of over 600 organic compounds http://www.zirchrom.com/organic.htm

Dissociation Constants Of Organic Acids And Bases This table lists the acid-base dissociation constants of over 600 organic compounds, including many amino acids. All data apply to dilute aqueous solutions and are presented in the form of pK a , which is the negative of the logarithm of the acid dissociation constant K a Molecular formula Name Step T I °C pK a CH O Formic acid CH N O Urea CH N Methylamine C HCl O Trichloroacetic acid C H Cl O Dichloroacetic acid C H O Glyoxylic C H O Oxalic acid C H BrO Bromoacetic acid C H ClO Chloroacetic acid C H IO Iodoacetic acid C H OS Thioacetic acid C H O Acetic acid C H O Glycolic acid C H N Ethyleneimine C H NO Acetamide C H NO Glycine C H O Ethylene glycol C H AsO Cacodylic acid C H N Dimethylamine C H N Ethylamine C H NO Ethanolamine C H NO S Taurine C H NS Cysteamine C H N 1,2-Ethanediamine C H NO Cyanoacetic acid C H NS Thiazole C H N 1H-Imidazole C H N S 2-Thiazolamine C H O Acrylic acid C H O Pyruvic acid C H O Malonic acid C H ClO 2-Chloropropanoic acid C H ClO 3-Chloropropanoic acid C H N Melamine C H O Propanoic acid C H O 3-Hydroxypropanoic acid C H O Lactic acid C H O Glyceric acid C H N Azetidine C H NO L -Alanine C H NO b -Alanine C H NO Methylglycine C H NO S Cysteine C H NO Serine C H NO S l -Cysteic acid C H N O Glycocyamine C H O Glycerol C H N Propylamine C H N Trimethylamine C H NO 1-Amino-2-methoxyethane C H NO Trimethylamine oxide C H N 1,2-Propanediamine

79. Conductivity Of Acids And Bases DoChem 104 Conductivity of acids and bases. An LED device or a meter deviceis used to study the conductivity of solutions of acids and bases. http://129.93.84.115/Chemistry/DoChem/DoChem104.html

Return to DoChem Index DMEX DoChem 104 Conductivity of Acids and Bases Description Set Hazards Precautions ... Key Words Description An LED device or a meter device is used to study the conductivity of solutions of acids and bases. Changes in conductivity associated with the titration of sulfuric acid by barium hydroxide are studied. Go to Top Set Free electrons (as in a metal), free ions, or some other mobile charge carrier must be available to sustain an electric current. A solution that contains ions will conduct electricity. The amount of electricity that will flow through a solution depends primarily on the numbers of ions present: the greater the number of ions, the greater the amount of electricity which will flow. This can be observed by using a conductivity apparatus. The amount of electricity flowing is indicated by the brightness of the light bulb, the LED, or the meter reading. A strong electrolyte ionizes to a large degree. When a strong electrolyte is also soluble, its solutions contain many ions, conduct electricity well, and cause the lamps in a conductivity apparatus to burn brightly. A weak electrolyte dissociates only slightly in solution, forms fewer ions, and causes the light bulb to glow dimly. A nonelectrolyte has very few ions, and the light bulb will not glow. In this experiment the conductivity apparatus allows us to distinguish between strong and weak acids or bases. Acids and bases react to form salts and water. Salts are nearly always strong electrolytes.

80. Standardization Of Acids And Bases Return to DoChem Index EXPT DoChem 102 Standardization of acids and bases. DoChem102 Standardization of acids and bases. Titration Skills Checklist. http://129.93.84.115/Chemistry/DoChem/DoChem102.html

Return to DoChem Index EXPT DoChem 102 Standardization of Acids and Bases Description Set Hazards Precautions ... Key Words Description Solutions of known concentration are prepared by dissolving measured masses of standard acids in distilled water. The concentrations of unknown solutions of sodium hydroxide are determined by titration. Go to Top Set An acid solution reacts with a base solution in a "neutralization" reaction. The pertinent chemical reactions in this experiment are: O **Visual here. or Figure V102V1 H C O O + Na C O H SO O + Na SO H + OH O The volume of solution required for such a reaction to go to completion may be measured using a buret. A color change in an added chemical indicator signals an end point. It is selected to indicate that neutralization has taken place. This end point may not be the same as the stoichiometric or equivalence point; given an appropriate selection of indicator, the difference in volume between these two points should be negligible. In this experiment, a solid acid is titrated with sodium hydroxide to the faint pink phenolphthalein color. Once the concentration of the NaOH is known, it may be used to calculate the concentration of other acids.

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