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Acids and Bases

Equilibrium Equation

Could you please explain what happens when hydrogen ions are added to a mixture of barium chromate (S) and chromate ions (AQ). Would there be a precipitate and, if not, why?

Diprotic acid with ka1 and ka2

A diprotic acid, H2A, has the following ionization constants: Ka1 = 1.1E-3 and Ka2 + 2.5E10-6. In order to make up a buffer solution of pH 5.80, which combination would you choose, NaHA/H2A or Na2A/NaHa? What is pKa of the acid component? I don't understand this problem at all! I know that a diprotic substance has something i

Buffer NH3 and NH4Cl

I am really having problems with this problem: Calculate the pH of the 0.20 M NH3 and 0.15 NH4Cl buffer. What is the pH of the buffer after the addition of 10.0 mL of 0.10 M HCl to 57.5 mL of the buffer. The first part was fair enough, I got 9.35 pH, which is correct. The set up of the second part is tripping me up, I ca

Molarity, electron configuration, and concentration

Question 31 What is the molarity of a solution in which 26.0 grams of BaCl2 (molar mass = 208.2 g/mol) are dissolved in enough water to make 450.0 mL of solution? 0.278 M 0.617 M 1.00 M 3.41 M Question 32 Which element has the following electron configuration? 1s22s22p63s2 Na Mg

Calculating acid dissociation constant

A diprotic acid, H2A, has the following ionization constants: Ka1 = 1.1E-3 and Ka2 = 2.5E-6. In order to make up a buffer solution of pH 5.8, which combination would you choose, NaHA/H2A or Na2A/NaHA? I know the solution is Na2A/NaHA, but I am not sure why. What is the pKa of the acid component?

NaOH to prepare 576 ml of a solution

How much NaOH is needed to prepare 576 mL of solution with a pH 10? Is it possible to calculate concentration of a solution, OH- concentration, and H+ concentration from just a pH given (no specific base or acid)? Is the concentration of a solution the same as the concentration of [OH-] or [H+]?

Chemical quantities

I need the exact steps that are involved in solving each of these problems and how to arrive at the answers step by step so I can grasp the concept clearly. Thanks. It is very important that I see each step. 1. The gaseous hydrocarbon acetylene, C2H2, is used in welders torches because of the large amount of heat released w

Acidity and Undissociated Acid

A weak acid has a pKa of 3.654. If the solution pH is 3.741, what percentage of the acid is undissociated? A weak acid has a pKa of 5.857. Calculate the pH of a solution in which the ratio of the concentrations of acid anion to undissociated anion ([A-]/[HA]) equals 7.555.

Chemical equations- the Ka and Henderson Hasselbalch equation

Please help, I'm really stuck on the following:- A weak acid has a PKa of 7.713. Calculate the pH of a solution in which the ratio of the concentrations of undissociated acid to acid anion ([HA]/[A-]) equals 8.441 also Calculate the PKa of a weak acid given the information that a 0.652 M solution has a pH of 2.882

Oxidation and reduction problems

1) When iron is oxidized in the presence of nitric acid, three products are formed: iron(III) nitrate, nitrogen dioxide and water. Write and balance the equation for this reaction. Then calculate how many grams of water are formed if 500 grams of iron are reacted with 500 grams of nitric acid. 2) When iron is oxidized in th

Aqueous Solutions

The only possible ions in an aqueous solution are ion, barium, carbonate, chloride and nitrate. The following are observed: i) the original solution contains only dissolved species. ii) adding silver ion to the solution produces no precipitates. iii) adding sulfate ion to the original solution produces a white precipitate

Equilibrium no longer exists - reaction of opening a soft drink bottle

14. In a normal bottle of Coca Cola before it is opened, the following equilibrium exists: H2C03 <=> H+ +HCO3-; Ka = 4.2 x 1 O-7 Once the bottle is opened, this equilibrium no longer exists. Explain what happens, and write a new equilibrium expression showing what happens. I'll give you a hint; there is more than one equil

Equilibrium; Ionization; Concentration

Please see the attachment for complete information. 15. Into a 5.0 liter flask was placed 35.7 g of PCI5 . The flask and contents were heated to 250 0 C, and then held at temperature until the following equilibrium was established: PcI5 (g)< > Pc13 (g) + Cl2 (g) It was then shown by analysis that 875 g of Cl2 was pesent

Stoichiometric Problem

Brass is an alloy of copper and zinc.When ground into a fine powder,then added to hydrochloric acid solution,a single replacement reaction occurs with one of the metals.A soluble salt and hydrogen gas are produced. A)The balnce equation for the reaction that occurs? B)If a 60.0 g sample of the alloy contained enough of the m

Solutions/Acids/Bases

What volumes of 0.50 M HNO2 and 0.50 M NaNO2 must be mixed to prepare 1 liter of solution buffered at Ph of 3.55?

Acid-Base Reaction Problem

An aqueous solution contains dissolved C6H5NH3Cl and C6H5NH2. The concentration of C6H5NH2 is 0.50 and pH is 4.20. a. Calculate the concentration of C6H5NH3+ in this buffer solution. b. Calculate the Ph after 4.0 grams of NaOH(s) is added to 1.0 L of this solution. Neglect any volume change.

Acid Equilibrium: Titratable Acidity

Question: If 500 mg/L lactic acid is added to pure water and you add NaOH until the pH = 3.1, what are the final amounts of each species in the acid equilibrium? What is the titratable acidity? The formula for lactic acid is C3H603, with a dissociation constant, pKa = 3.86. The formula for tartaric acid is C4H606. We us

Spectator Ions Questions

1) How many moles of chloride ions are in 250.0mL of a 0.450M calcium chloride solution? 2) Identify the spectator ions for the reaction: CuBrsub2 (aq) + Lisub2CrOsub4(aq) -> CuCrOsub4(s) + 2LiBr(aq)

Acid / Base Reactions (Moles, Volume etc.)

4. a) Write the equation for the reaction of sulfuric acid with potassium hydroxide. b) If Ms. Chemist has a solution of potassium hydroxide that is 0.68 M, what is the volume (in mL) of the base needed to react completely with 55.0 mL of 2.45 M sulfuric acid? c) How many grams of acid were needed to make up the acidic sol

Solvents and solubility rules

21. One gram of NaCl and one gram of sand are added to 100mL of water. What is the solvent? NaCl Sand Water The Na and Cl ions 22. The gradual mixture of one gas with another by kinetic energy is termed diffusion. True False 23. Which of the following compounds is an acid? H2O N2

Calculating Ksp

1. Calculate the Ksp of a saturated solution if it contains 0.0001 M Pb2+. 2. CH2ClCooH(aq) --(Forward/Reverse reaction)--H+ (aq) + CH2ClCOO- (aq) Calculate the value of Ka(acid) if a 0.1 M solution of CH2ClCOOH has a pH of 2. (a.) given pH, what is the [H+]? (b.) given [H+], what is [CH2ClCOO-]? (c.) Wha

Ostwald process

Using Ostwald process, what mass of nitric acid could be produced from 75.0 g of N2 and 50.0 g of H2? I have all the molar masses, the limiting factor, and the ratio of the limiting factor to the product. How do I put this information into an equation to come up with a reasonable answer?

Acid-Base Reactions

1) Show the calculation for determining the mass of NaOH pellets required to prepare 250mL of 0.10M NaOH. 2) What substance is the proton donor and which is the proton acceptor in NaOH and KHP? 3) What is an equivalence point in a titration?

Percent by mass of palmatic acid in Commercial steric acid

Commercial steric acid (C17H35COOH) contains palmatic acid (C15H31COOH) as an impurity. If a 1.115 gram sample of commerical steric acid is dissolved inm 43.95 grams of benzene, the freezing point is found to be 5.072 degrees celcius. If the freezing point of pure benzene is 5.533 degrees celcius what is the percent by mass of

Formation of FeCl3 using HCl

I know that: 2HCL +Fe(s)= FeCl2 + 2H under normal conditions. I want to know if the concentrations or conditions can be altered to produce: 3HCl + Fe(s)=FeCl3 + 3H using NO other reactants (catalysts may be used).

Can acid be used to catalyze the formatin of Iron (III) ion (aqueous)?

From what I have gathered, it appears that the reaction between Iron and certain acids can produce either Fe2+ OR Fe3+ ions. For example, I believe that HCl and Fe(s) will produce hydrogen and either FeCl2(aq) AND/OR FeCl3(aq). Similiarly, the reaction between Fe(s) and H2SO4 will produce hydrogen and Iron (II) sulfate(aq) A

Writing Chemical Equations

Write a chemical equation for the following reactions: i) zinc sulphate + barium nitrate ii) gold (III) sulphate + barium chloride iii) zinc + mercourous nitrate iv) tin + antimony (V) chloride v) calcium + water vi) ferrous bromide + phosphoric acid vii) calcium carbonate + hydrobromic acid &#8594;