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Acids and Bases

Using Water and Calcium Phosphide to produce phosphine

I have a selection of apparatus and materials that I could use to prepare a gas jar of dry phosphine. I have the following pieces of apparatus to use:- Wash bottle Polythene connectors Dropping funnel with rubber stopper Bent glass tube Filter funnel with paper U-tube Porcelain boat Gas jar Round bottomed flask w

Balanced Equation for Sodium Bicarbonate and Sulfuric Acid

Sodium bicarbonate was added to an unlimited amount of sulfuric acid undergoing a reaction to produce sodium sulfate plus carbonic acid (which turned in to water vapor and carbon dioxide upon heating). Please provide a balanced equation for this reaction.

Reduction Potential

Observations: 1) A reacts spontaneously with 1mol/L BNO3, 1mol/L D(NO3)2 and dilute sulfuric acid.A does not react with 1mol/L C(NO3)2. 2) B does not react with any of the 1mol/L solutions above or the dilute sulfuric acid. 3) C reacts spontaneously with dilute sulfuric acid and with 1mol/L solutions of all the other metallic

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 Problems

Please provide 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. 1. The gaseous hydrocarbon acetylene, C2H2, is used in welders torches because of the large amount of heat released when acetylene burns with oxygen, producing ca

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; 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

Concentration of an Acid after Titration

During titration the following data were collected. A 50mL portion of an HCl solution was titrated with 0.50 M NaOH. It required 200mL of the base to neutralize the sample. How many grams of acid are in 500 mL of this acid solution? The attached solution describes all steps of the required procedure to find out the unkonwn a


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

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?

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

Converting Units of Measure and Chemical Formulas

1. How many grams of CI2 can be prepared from the reaction of 15.0 g of MnO2 and 30.0 g of HCl according to the following equation? 2. How many mL is 0.005 L? 3. Give the number of protons (p), electrons (e), and neutrons (n) in one atom of chlorine - which has the symbol Cl. 4. A newborn baby weighs eight and one ha

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;

Solubility at Equilibrium of AgOH

10.0 mg of AgOH(s) is added to 350.0 mL of water with an initial pH of 11.00. The solubility equilibrium constant for the dissolution of AgOH (s) is Ksp = 1.5 x 10^-8. Determine the concentration of [Ag +] and the final pH at equilibrium.

Boric Acid and its Conjugate Base

Boric acid, B(OH)3, is an acid that acts differently from normal Bronsted-Lowry acids. It reacts with water to form B(OH)4- and H30+. a) Draw Lewis structures and indicate the shapes for B(OH)3 and B(OH)4- b) What is the species that donates a proton to water? c) Can B(OH)3 be described as a Lewis acid?

Amount of Coal Needed to Produce a pH of 2

How many metric tons of 5%-S coal would be needed to yield the H2SO4 required to produce a 5.0 cm rainfall of pH 2.00 over an area of 100 square kilometers? Hint: calculate the volume of rain, mol H+, mass of S, mass of coal. If you could work out the problem for me, that would be great! It makes it easier to understand.

How Many Grams of Molecules Can Be Formed?

In the lab you add excess hydrochloric acid to 2.65g of Na2CO3. The balanced reaction is 2HCL (aq) + Na2CO3 (aq) ---> CO2 (g) + H20 (l) + 2NaCl (aq) 1) Identify the type of reaction 2) How many grams of gas molecules can be formed from this much Na2CO3? Show the calculation of the molar masses of all necessary substances