Acid Definition and 698 Threads

"By taking a little apple cider vinegar before a meal, you can increase stomach acidity and thereby improve digestion and nutrient uptake. " But since vinegar is less acidic than stomach acid wouldn't it follow that vinegar would reduce stomach pH? (unless the watery contents of vinegar flux...

Procedure: 1. Pipette 25 cm3 of ethanoic acid into a conical flask 2. Titrate against 0.1M sodium hydroxide solution in the burrette, using phenolphthalein as indicator. 3. Pipette further 25 cm3 of ethanoic acid into the solution after titration and mix throughly. Questions: 1. what is...

I currently have a set up where I have attached a permanant magnet dc motor to a bicycle. The motor is attached through a diode to a 12v regulator and then to a 12v to 240v inverter. Everything works fine and I can power up my devices. But I have been told that if I connect my 12V lead acid...

OK, so I just got out of an organic chemistry exam. I feel pretty good about every question except one which I did not know - please help me put my mind at ease! What is the major product of the reaction of this molecule: http://img216.imageshack.us/my.php?image=stupidthingdw3.jpg with...

Homework Statement Titrating .1006M CH3COOH with .2012M NaOH. pKa=4.74, Ka=1.8*10^-5 What is the pH at the equivalence point of the titration? Homework Equations pKa = -log(Ka) pH = -log[H+] The Attempt at a Solution Alright, after setting up an ICE table (in order to find...

the acid solution in a fully charge lead storage cell contains 33% h2so4 by weight and has a density of 1.25g/ml. cALculate its molarity

I'm having some trouble understanding what happens when Zinc and Hydrochloric acid are reacted with Copper Sulfate as a catalyst. I *think* the Copper ion gets electrons from the zinc and turns into straight copper which leaves zinc free to react with the chlorine to form zinc chloride. Does...

Why is the enthalpy of neutralisation of a strong acid mixed with a strong base always the same, no matter what acid and base combination you use, provided they are 'strong' acids and bases? Am I right to say that this value is accepted as -57.35 kJmol-1? Thanks for any help, Isaac.

hi i have the following reaction isobutyric acid + 2-methoxyethanol <-> 2-methoxyethyl-2-methylpropanoate but i don't know all of the by-products. please help thanks edit: i think is only water and some unreacted reactants?

Homework Statement If Lovastatin were heated in dilute aqueous acid, what would the molecular weight of the product be? (The large of the two products. Assume that there is no hydration of the alkene functionalities.) Homework Equations N/A The Attempt at a Solution I drew...

How can I calculate the amount of citric acid to add to a solution of a given pH, to achieve another value of pH?

Homework Statement Stearic acid, nature's most common fatty acid, dimerizes when dissolved in hexane: 2C17H35COOH --> (C17H35COOH)2 H°rxn = -172 kJ The equilibrium constant for this reaction at 28°C is 2900. Estimate the equilibrium constant at 38°C. 1) 4.7 *10^5 2) 1.9 * 10^3...

Alluminium + Nitric Acid = Alluminiumnitrate Whats the chemical formula for this equation ? :) Thanks

Homework Statement A buffer is prepared by dissolving 1.00 mole HLac (with a ka=8.0x10-3) and 1.00 mole of sodium lactate (NaLac) in enough water to form one (1) liter of solution. Calculate the [H+] and the pH of the buffer. 36 minutes ago - 3 days left to answer. Additional Details 12...

[SOLVED] Titration Lab Homework Statement How many grams of pure citric acid in the juice solution when 4.00 g of the juice crystals are dissolved in 100.0 mL solution? The juice solution is titrated using a given solution of sodium hydroxide. The NaOH is titrated into 10 mL of the juice...

I have to examine the amino acid sequences of a segment of each of the following proteins: lysine, alanine, leucine, arginine, isoleucine, proline, glycine, histidine, and serine. Provide, in order, a list of the following potential components. a. tRNA nucleotides (in the anticodon loop) that...

[b]1. The dipole moment of a peptide bond is 3.7 Debye in water. Assuming that a hydrogen bond is essentially a dipole-dipole interaction, estimate the energy of a hydrogen bond between two peptides in water and in the interior of a protein (neglect the competing interactions with the solvent)...

Would a lack of vitimin b12 and folic acid make some one very tired?

Homework Statement How does sulphuric acid catalyze the preperation of ester? The Attempt at a Solution Does it cleave the molecule that becomes the ester?

Homework Statement We did a lab in class about weak acid/strong base titration, but I'm having a bit of trouble. We we only given the molarities of an unknown weak acid and a strong base (NaOH) and the pH of six different mixtures containing different mL of the two, which is below: Test...

Can a solution of 35% sulfuric acid and 65% water be safely stored in a plastic bottle? That is, does sulfuric acid of this concentration react with any or all plastics? if plastic is not acceptable, what type of storing container could safely contain the acid? If interested, what I have in...

Homework Statement A beaker with 135 mL of an acetic acid buffer with a pH of 5.00 is sitting on a benchtop. The total molarity of acid and conjugate base in this buffer is 0.1 M. A student adds 7.80 mL of a 0.400 M solution to the beaker. How much will the pH change? The pKa of acetic acid...

A beaker with 135 mL of an acetic acid buffer with a pH of 5.00 is sitting on a benchtop. The total molarity of acid and conjugate base in this buffer is 0.1 M. A student adds 7.80 mL of a 0.400 M solution to the beaker. How much will the pH change? The pKa of acetic acid is 4.76. What I did...

Hi I have been trying several days to solve this problem. But i can't find the procedure to solve this weak acid and weak base problem. I will really appreciate some help. What is the pH of a soft drink in which the major buffer ingredients are 6.90 g of NaH2PO4 and 5.70 g of Na2HPO4 per...

Hi I have been trying several days to solve this problem. But i can't find the procedure to solve this weak acid and weak base problem. I will really appreciate some help. What is the pH of a soft drink in which the major buffer ingredients are 6.90 g of NaH2PO4 and 5.70 g of Na2HPO4 per...

Homework Statement A solution is to be buffer at pH = 3:35 with formic acid and formate. (a) How many moles of formic acid and sodium formate are needed if the solution is to change pH by < 0:02 for the addition of 0.02 moles of strong acid? i need help how to set up a problem like...

[SOLVED] magnesium and acid rates reactions im producing an investigation in the reaction between magnesium a solid metal, and acids of varying concentration, pH and temperatures. these variables are to produce results for comparison. however i am unsure about what apparatus would be most...

Homework Statement A 0.307g sample of an unknown triprotic acid is titrated to its equivilence point using 35.2ml of 0.106 M NaOH. Calculate the molar mass of the acid. Answer is in g/mole. Homework Equations The Attempt at a Solution I just don't know where to start with this...

Homework Statement I've been working on this problem and am having issues with some of the problems... all we learned was that EQ is pH= pka and at eq and EQ1/2 is pk1+pk2/2 which can't even be applied to this question due to x values. I would GREATLY appreciate ANY help/guidance/etc...

25 mL of 0.1 M HOAc are titrated with 0.15 M NaOH. What is the pH at equivalence? I know that the pH at start will be greater than 1.0 and the pH at equivalence will be greater than 7 since its a titration of a weak acid and a strong base. But what I don't know is whether or not there is a...

Hey Guys, I seem to be having some problem with this question. Can anybody help me out? Each of the following salts can be prepared from an acid and a base. Write the balanced molecular equation and net ionic equation for the preparation for each. Indicate states of the reactants and the...

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...

If I have a mixture of benzoic acid and benzil, and I add dichloromethane to it and extract it using sodium hydroxide, the benzoic acid reacts with the sodium hydroxide to form sodium benzoate, but what does the benzil react with. I know that its in the organic layer because it's neutral but...

Hello, I did a lab on the recrystallization of benzoic acid. My solvent was hot water and used charcoal to adsorb any color impurities. I am trying to figure out how I should write a reaction and a mechanism for this. Is there even a reaction and mechanism I can write for this? Any...

Why is oxalic acid called ethane-dioic acid even if it has nothing else but 2 carboxylic group??

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...

Homework Statement I'm just checking over the equation/reaction for butyraldehyde's solubility in H2SO4. Homework Equations See below. The Attempt at a Solution Will it be CH3CH2CH2C(=O)H + H2SO4 --> HSO4- + _________(+) __________O-H -----------|| CH3CH2CH2C-H ? Thanks.

I have a bottle of 100% pure citric acid. I would like to know how to make a 15% solution of citric acid from this.

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...

Homework Statement I just wanted to review what happens when methyl benzoate dissolves in sulfuric acid (the ionic species that arise). My workings/reasonings are below. Homework Equations See below. The Attempt at a Solution After the ester in placed in the acid, the...

Can somebody tell me the color the following items turn when purple Cabbage Indicator is added: Water Hydrogen peroxide Isopropyl alcohol Saline solution Aspirin Pepto-Bismol Alka-Seltzer Tonic water Vinegar and can you tell me if the items listed above are Acid or Base or Neutral...

A couple of questions: 1) How do I minimize it? 2) Would 5-6 small meals per day be a better digestive option? 3) Would a vegetarian diet cure acid reflux?

i'v synthesized benzoic acid from benzyl alcohol and i have a theoretical value for the yield and and experimental yield of impure acid. Theoretical Yield = 5.93g Impure Yield from experiment = 6.13g Now, my paper asks for the percentage yield of my impure acid, how does that work? If...

An experiment was carried out in class. Basically, Baking Soda was added to different concentrations of Ethanoic Acid. The plot of 'Maximum Foam observed' vs. 'concentration of the Acid'. The curve went up but then dropped noticeably! :confused: So basically, with high concentrations or low...

I did an experiment in one of the labs and I have a question I need to figure out. The experiment was the porduction of p-acetylaminotoluene, from p-toluidine. My question is we used acetic acid and acetic anhydride, but which is the acetyalting species. I thought of looking at the...

Why does oxidizing nature of nitric acid gets reduced on dilution?

Hello people...could u help me pls...coz i am rly stuck in these thing like calculations...i know all right answers but i am not too sure how to get them...please if somebody of us has a few minutes could u help me with that? Thank you very much. 1., When 0.25 g of sodium metal was added...

Chemistry questions Q1: Calculate the amount of 6M HCl that would be required to neutralize and acidify (to ~pH2) the reaction mixture of 1g Benzaldehyde and 2mL 10M KOH. I think this is the chemical equation: Benzaldehyde + KOH + H+ -> Benzyl Alcohol + Benzoic Acid Q2: 64% yield of 1,1...

[Chemistry Lab] Cannnizzaro Reaction Hi! I am having some questions about my chemistry lab. In the lab we are given 1 of the 5 unknown aldehyde (benzaldehyde, anisaldehyde, nitrobenzaldehyde, chlorobenzaldehyde, and dimethoxybenzaldehyde) and reacts it with methanol and KOH to undergo...

Sorry, I'm not much of a biology expert, but I was looking into the interactions between b5 and omega 3 fatty acids. I wanted some help clarifying this. http://www.pdrhealth.com/drug_info/nmdrugprofiles/nutsupdrugs/pan_0196.shtml Does that imply that it breaks down fatty acids and uses them as...