What is Acids and bases: Definition and 49 Discussions

An acid–base reaction is a chemical reaction that occurs between an acid and a base. It can be used to determine pH. Several theoretical frameworks provide alternative conceptions of the reaction mechanisms and their application in solving related problems; these are called the acid–base theories, for example, Brønsted–Lowry acid–base theory.
Their importance becomes apparent in analyzing acid–base reactions for gaseous or liquid species, or when acid or base character may be somewhat less apparent. The first of these concepts was provided by the French chemist Antoine Lavoisier, around 1776.

It is important to think of the acid-base reaction models as theories that complement each other. For example, the current Lewis model has the broadest definition of what an acid and base are, with the Brønsted-Lowry theory being a subset of what acids and bases are, and the Arrhenius theory being the most restrictive.

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  1. stuidvkook

    Chemistry Bronsted-Lowery Help: Understanding HCOOH + CN- and H2O + HCO3- Reactions

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  2. StarChem

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  3. SilverSoldier

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    Suppose we add a weak acid HA into pure water, so that upon addition its initial concentration is c. The following equilibria should establish in the system. $$\text{HA}+\text{H}_2\text{O}\rightleftharpoons\text{H}_3\text{O}^++\text{A}^-$$...
  4. sergey_le

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  5. R

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  6. sidt36

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  7. T

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  8. E

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  9. Titan97

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  10. N

    When to Use Kw & Ka for Acid Dissociation Calculations

    So I've learned that in strong acids that dissociate completely, the concentration of H+ is the same as the concentration of the initial solution. So 1M of a strong acid will create 1M of H+, meaning the pH is 0. I've also learned that in weak acids, the whole thing doesn't dissociate. I have...
  11. Dong Aleta

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  12. Dong Aleta

    A question regarding the definition of acids and bases

    Hi! I just read in an inorganic chemistry book (by Whitten, et al.) that acids are defined as substances that produce H+ ions in dilute aqueous solutions, and bases are those that produce OH-. To me, this definition implies that a substance that has yet to produce an H+ or an OH- can already be...
  13. G

    What is the common property shared by all acids that leads to their definition?

    I've written the following brief history on how the definition of acids and bases change over time. Lavoisier came up with his definition circa 1776 in that 'p is acidic iff p contains much oxygen' and that held sway for 30 years[1] until it was falsified by Davy in 1810[2] who demonstrated...
  14. V

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  15. J

    Procedure of preparation of HCl

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  16. iwantcalculus

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  17. C

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    Homework Statement what is the H, Oh , ph and poh for a 0.048 mol/l solution of benzoic acid? C6H5COOH Homework Equations Ph +poh=14 Ph=-log(h30+) H30=10^-ph The Attempt at a Solution I thought maybe u need to separate benzoic acid into its ions and then use the molar ratio to...
  18. 2

    Calculating H3O+ Concentration for Acetic Acid Solution | Ka = 1.8 x 10-5

    Homework Statement What is the H3O+ concentration of a 0.100 M acetic acid solution (Ka = 1.8 x 10-5)? a. 1.8 x 10-5 b. 1.8 x 10-4 c. 1.3 x 10-2 d. 1.3 x 10-3 e. 0.9 x 10-3 Homework Equations The Attempt at a Solution so the question is supposed to be D. but I thought that...
  19. K

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  20. J

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  21. M

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  22. K

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  23. R

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  24. D

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  25. P

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    Homework Statement I'm having problems understanding amphoteric acids and bases. I know amphoteric means that it can act as an acid or base, but when the question asks me to write the equation to support this statement, I always get it wrong :confused: Homework Equations HSO4^-1 is an...
  26. U

    Understanding Lewis Acids & Bases: HCl, H2SO4, H3PO4, CO2, HCN

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  27. B

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    Sorry guys, I can't seem to grasp the concept: It deals with acids and bases. When the acid donates the proton, to the base, how do we know how many is transferred and how many the base can accept? This is where I am stumped. Homework Statement What ions are formed when nitric...
  28. P

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  29. L

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  30. L

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    Homework Statement I'm a little confused, let's say i do a titration curve for a weak acid, at some point there's a buffering range near the pKa. Like i know that if we add a strong base like NaOH to acetic acid in a water solvent, then the OH- will combine with the H+ (hydronium ion) which...
  31. W

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    Homework Statement You prepared a reaction table for 10.0 mL of 0.1 M NH4Cl with 5.0 mL of 0.1 M NaOH. Please choose all of the following that describe the solution that was produced. The choices are: 1. a solution containing only a strong base 2. a solution containing a weak acid and a...
  32. L

    Differentiating Acids and Bases Based on Chemical Formulas

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  33. S

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  34. D

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  35. D

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  36. C

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  37. P

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  38. L

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    Anyone clever with bronsted acids and bases? I'm pretty new in chemistry, but I'm trying to learn. Right now I'm suppose to classify some species as either bronsted acids or bases, or even both. For example 1. Water 2. OH- 3. NH4+ 4. HCN 5. HBr 6. NH3 Hope someone can help...
  39. B

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  40. D

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    I have problem in complete understanding these concepts especialy in organic chemistry. Inorganic was simple HaON, HCl and similar, but now in organic chemistry Acids and Bases concept and fast determining of those is killing me :(. Is there a place on internet with good tutorial covering...
  41. A

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  42. D

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  43. D

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    Uggh finally did all the chem problems and studied for the upcoming final but there are 2 questions left unanswered. MAybe someone can help me out with this: If given a lists of acids, how would one know which 1 is the weakest conjugate base? For example, HF, HNO_2, H_2CO_3, H_3BO_3, HCl...
  44. J

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  45. J

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  46. J

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  47. J

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  48. E

    Explaining Acids and Bases to a Six-Year-Old

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