What is Acid base: Definition and 38 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. red65

    Very confused about Naunyn definition of acid and base

    First so that you can have some background I'd like to share an excerpt from the online lecture I'm studying. Here's a sample: "1880-Arrhenius defines an acid as a substance that , when dissolved in water, produces an increased concentration of hydrogen ions. 1900-Naunyn combines Arrhenius'...
  2. S

    Chemistry Can anyone check my answers for these equilibrium problems?

    The following are my works for the problems: I put squares on my final answers! Thank you!
  3. J

    Calculate pH of NaF Solutions | 0.30 M

    Homework Statement Calculate the pH of the following solutions: (caution: these are hydrolysis reactions) a. an 0.30 M solution of NaF Homework Equations I think by hydrolysis reactions they mean that each of the given compounds is combined with $H_2O$. Then for a) NaF + HF <-->...
  4. J

    Calculate the pH of a 0.20 M solution of iodic acid (HIO3).

    Homework Statement Calculate the pH of a 0.20 M solution of iodic acid ##(HIO_3)##. ##K_a## for iodic acid is 0.17 Homework Equations ##K_a = \frac{[H^+][IO_3^-]}{[HIO_3]}## The Attempt at a Solution ##[HIO_3] = 0.20## M. The concentration of ##[H^+]## and ##[IO_3^-]## should be the same...
  5. A

    Why Does Alka-Seltzer Acidify Water but Act as an Antacid?

    Hi everyone. I was testing the pH of water that had alka seltzer placed in it. I used Bromothymol blue indicator to see the pH. The color changed to yellow, which suggests that the water was now acidic. I assume this is because of the CO2 bubbles that form which can acidify the H2O. Am I...
  6. Grant

    Determination of an Acid (Monoprotic) by Titration Lab

    I tried looking for my unknown (209.70 g/mol) online and couldn't find it. The closest I found were H4O7V2(217.907 g/mol) and HCl2I(198.819 g/mol), but I know I am correct to a 2.7% accuracy. What other lists can I use to solve this?
  7. V

    Why don't acids react with neutral salts in solution?

    Hi I am new to the concept of neutralization. My teacher told me that acids do not react with neutral salts. I want to know why not. If both are dissolved in water and both completely dissociate, why can't the ions of acid and salt exchange and perform a double displacement reaction. Moreover I...
  8. caters

    Chemical water treatment: Acid base reaction

    I was thinking of a hypothetical waste system that uses nanotechnology to its advantage. At the individual level, waste just passes through into pipes when flushed like it normally does. But once it reaches the water treatment plant there is an initial filter to catch solid waste(in other...
  9. V

    Acid-Base Equilib: Solving Homework Problem

    Homework Statement To unclog a drain you add 26g of sodium hydroxide to 150mL of water. Calculate the pH and pOH for the solution you prepared. Can someone tell me if I'm doing it right. Homework EquationsThe Attempt at a Solution n = m/M n = 26/40 n = 0.65mol for 0.15L Does this mean that I...
  10. donaldparida

    What is difference between pH and pKa , pOH and pKb?

    Do pH and pKa refer to the same concept? The same question for pOH and pKb also. What does kWh actually mean. In have read that it is the ionic product and is the product of [H+] and [OH-] but what does it indicate. Does it have any full form?
  11. UMath1

    Ka vs Kb Weak Acids: Acetic Acid Low Ka, Lower Kb?

    Since Acetic Acid is a weak acid, it has a low Ka which means that the forward reaction is not favored as much as the reverse reaction. However, the Kb is even lower than the Ka...how is this possible? Shouldn't the Kb be higher to indicate that the reverse reaction is favored?
  12. B

    Acid-Base Reactions: Did the Solutions Neutralize Each Other? | Homework Help

    Homework Statement Student mix four reagents together, thinking the solutions will neutralize each other. The solutions mixed together are 50.0mL of .1 M HCl, 100mL of .2 M of HNO3, 500mL of .01 M CaOH, 200mL of .1 M RbOH. Did the acids and bases exactly neutralize each other? If not, calculate...
  13. vetgirl1990

    Which compound will be extracted in organic layer?

    I'm having a lot of trouble predicting which compounds would be extracted into which layer (organic vs. aqueous) using acids and bases. Using the solvents dichloromethane (which would form the organic layer) and sodium hydroxide (would form the aqueous layer along with water), I am asked to...
  14. RoboNerd

    Why is Pure Water Most Soluble for AgCl?

    Homework Statement In which one of the following solutions is silver chloride the most soluble? A) 0.181 M HCl B) 0.0176 M NH3 C) 0.744 M LiNO3 D) pure water E) 0.181 M NaCl Homework Equations the Ksp expression for the dissolution of AgCl is: Ksp = [Ag+][Cl-]The Attempt at a Solution...
  15. RoboNerd

    Question about acid and base multiple choice solving

    Homework Statement I found this problem online for extra practice for my AP Chem class. https://www.quia.com/files/quia/users/jpugteach/APChem/AP-Chem-Chapter-19-Graphs.pdf The problem in question is number 4. I do not understand how to solve it and why the answer D is correct. Homework...
  16. RoboNerd

    Question about acid and base indicators

    Homework Statement Methyl red has the following structure [not listed here on this post] Ka = 5.0 * 10 E -5 It undergoes a color change from red to yellow as a solution gets more basic. Calculate an approximate pH range for which the methyl red is useful. What is the color change and the...
  17. A

    How Do You Calculate pH and [OH-] for a Mixed NH3 and NH4Cl Solution?

    Homework Statement [/B] NH3(aq) is a weak base with Kb = 1.8*10-5, Calculate [OH-] in a solution that is made by mixing togeather 500ml of 0.20M NH3(aq) and 500ml of 0.20M NH4CL(aq), what is the value of Ph?Homework Equations Henderson Hasselbalch: ph = Pka + log([conj.base/acid]) As well as...
  18. UchihaClan13

    Acid Base Confusion: Solutions to Common Questions

    Hey all! I have a silly doubt In acids and bases As you guys know The concentration of H+ ions For a weak acid Which does not undergo Complete dissociation Is given by mod H+=square root of Ka times C Where C is the initial concentration Of the acid And k is the ionization constant In the same...
  19. fairburn96

    HSAB: Hard Soft Acid Base | Ferdinand's Curiousity

    Hi guys, my name is ferdinand. I'm curious about HSAB, especially to predict where the reaction goes. Exp: HI + NaF >>> HF + NaI H is hard acid I IS soft base Na is hard acid F is hard base, and HF Is hard.hard NaI Is hard soft. The reaction will goes to right or left? And why? And since hard...
  20. H

    Acid Base Theories: Bronsted-Lowry vs Lewis

    what theories out of the major two ( Bronsted-Lowry Theory of acids and bases and The Lewis Theory of acids and bases) should we use in common problems, and which one is more reliable ?
  21. Q

    Acid Base Titration: Calculating Absolute Error

    i am doing my lab report and i just want to know how to calculate the absolute error of the acidic concentration and thank you.
  22. L

    Hard soft acid base theory, i'm not understanding it

    Homework Statement the question asks to determine if the equilibrium is greater, equal or less than 1. one of the equation is the following: [CuI4]2- (aq) + [CuCl4]3- (aq) ↔ [CuCl4]2-(aq) + [CuI4]3- (aq) Homework Equations The Attempt at a Solution the solution given was...
  23. A

    How Much Stomach Acid Can One Antacid Tablet Neutralize?

    Homework Statement Assuming stomach acid is 0.1 M HCl(aq), what volume of stomach acid can be neutralized by one antacid tablet? We have the titration curve we got with .5M HCl titrating a tablet dissolved in 100ml distilled water Homework Equations ? The Attempt at a Solution ?
  24. J

    Chemistry Find the molecular mass of acid in acid base neutralization

    Homework Statement 1.5000 g of diprotic weak acid H2A was dissolved in 100.00 mL volumetric flask. 25.00 mL aliqouts of this solution was titrated with a monoprotic strong base NaOH (0.08000 M). The titre volume of NaOH was 40.00 mL. Calculate the molecular weight of H2A. Homework...
  25. P

    Chemistry How Did My Professor Calculate 45 mmoles of Limiting Reagent in a Chemistry Lab?

    Homework Statement Hi. I'm reaady to panic right now so if anyone could please take the time to answer my question I would HUGELY appreciate it! I seriously need to get this done soon as I also have a test tomorrow and i just want to cry because I'm getting nowhere... We did a lab...
  26. H

    Acid-Base Reaction: Calculating PH of NaF Solution

    Homework Statement after titrating sodium hydroxide with hydrofluoric acid, a chemist determined that the reaction had formed an aqueous solution of 0.020 mol/l sodium fluoride. determine ph of the solution Homework Equations The Attempt at a Solution Ka of HF= 6.3X10^-4 NaOH +...
  27. D

    Acid-Base Titration: Calculating % Purity of Sodium Carbonate

    Hi. In class, i am required to perform a titration where i am given a solution of sodium carbonate and a solution of hydrochloric acid of known concentration. I am to use the acid to calculate the percentage purity of the sodium carbonate. Im not really sure how to go about doing this. The...
  28. T

    Experiment Volumetric analysis - Acid base

    Homework Statement Do not understand the question. 2. My Lab Results Topic : Volumetric analysis - Acid base purpose : To determine the exact concentration of a mineral acid, HXO4, and to determine the relative atomic mass of the element X. Materials : KA1 is a mineral acid, HXO4...
  29. K

    What Determines Acid and Base Strength in Bronsted-Lowry Theory?

    Hello everybody, I'm having difficulty understanding the rationalization behind the strengths of Bronstend Lowry acids and bases and my textbook isn't too helpful. Can someone please expalin to me: (1) What exactly is effective negative charge density? (2) how does electronegativiy correspond to...
  30. E

    Solve Acid Base Titrations: 0.700-M KOH & 0.350-M H2SO4

    Homework Statement Given H2SO4 + 2LiOH --> Li2SO4 + 2H2O, how many mL of a 0.700-M solution of KOH are needed to react with 235 mL of a 0.350-M H2SO4 solution? The Attempt at a Solution Really, I have none. My problem is that I don't understand what the question is asking. I could...
  31. P

    What is the Correct pH at the Endpoint of a Weak Acid Neutralization?

    Homework Statement You dissolve an unknown quantity of weak acid HA into 50 mL of water. It only takes 1 mL of 5 M NaOH to completely neutralize the acid. The Ka of the acid is 3.2 x10^-4. What is the pH at the endpoint?Homework Equations Ka * Kb = Kw pH + pOH = 14 p(of whatever) = -log(of...
  32. P

    How Do You Calculate pH After Adding NaOH to H2S Solution?

    Homework Statement A vessel contains 500mL of .1 molar H2S solution. For H2S Ka1 = 1 x 10^-7 Ka2 = 1.3 x 10^-13. What will the pH be when 800mL of .1molar NaOH has been added. Homework Equations ph = -log([H]) ph = pka + log(B/A)The Attempt at a Solution This is how I started, I found the...
  33. A

    Naturally occurring acid base buffering system in an organism

    I tried looking for this online, but didn't really find anything can someone help me out I need an example of a naturally- occurring acid-base buffering system in an organism
  34. P

    Acid-Base Reaction Q: Salt & Water Except What?

    I have a question concering acid base reactions. All strong acid-strong base reactions produce a water soluble salt and water with the exception of what? I need to know that along with the formula unit, total ionic and net ionic equation. Please any help would be appreciated. Thank you
  35. N

    What Is the pH After Titrating Butanoic Acid with NaOH?

    Hi. I am having trouble with acid-base titration excercises. 0.02 L butanoic acid @ 0.1 M is titrated with 0.01 L NaOH solution @ 0.1 M. The Ka of butanoic acid is 1.54X10^-5. Find the pH. The answer is 4.81. I know how to find the pH when no NaOH is added, but I really don't see how the...
  36. D

    Acid base titration problem. Need Help

    How many moles of H3O+ must be added to one liter of a solution to adjust the pH from 7.17 to 5.85? Correct answer 1.34E-6 (1.34 * 10-6) The correct answer is given, however I would like to know how to do this problem.
  37. M

    How Does Excess HCl Affect pH in Methyl Ammonia Titration?

    consider the titration of 50.0mL of 0.10 M methyl ammonia with 0.10 M HCl. Calculate the pH after 15mL of titrant= 11.05 25mL of titrant= 10.68 50mL of titrant= 8.98 60mL of titrant= ? At 60 mL there is an excess of 1 mmol of HCl. At this point do I say that the pH is 1 (-log of 0.10)...
  38. B

    How Do Acid-Base Titration Calculations Work?

    I have several questions. 1.)Supose [H+] is 100 times less than the ka for an acidic acid-base indicator (see Eq.2), and enough acid is added to the the solution to raise [H+] by a factor of 10,000. What value did the ration of the different colored forms of the indicator, [ln-]/[H ln], have...