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Acids and Bases

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


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;

Balanced Chemical Equations

Write balanced chemical equations for the following: Ionization in water of the weak acid HF Ionization in water of the strong acid HI Reaction of the strong acid HI with the strong base NaOH in water Interaction of the weak base C2H5NH2 with water. Ionization of the strong base KOH in water.

Ionic strength problem...

Human blood plasma is approximately 0.70% NaCl by weight. What is the ionic strength of blood plasma? I need a detailed explanation please- not just numbers! I am using this as a study guide for my final. Thnaks!!

Ph problem

A weak base with Kb=4.240*10^-7 is added to water to make a 2.00*10^-1 M solution. what is the pH? Since Kb is small, can assume that the dissociation is small relative to initial concentration of weak base.

2 titration

For which type of titration will the ph be basic at the equivalence point? Show work. Thanks

Reaction Types, Limiting Reagents and Yield Questions

Balanced Reaction: Ti(OH)4 + 2H2SO4 ---> Ti(SO4)2 + 4 H20 - Name each reactant,and product. What type of reaction is this? What is the limiting reagent? - How many grams of water can be produced from this reaction? Show the calcuation of the molar masses of the necessary substances before showing the calculation for theor

Calculating Concentration

What is the concentration of 25.0 mL of HCl if it is completely neutralized by 47.4 mL of 0.250 M NaOH?