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Acids and Bases

pH of Na2S and LiNO3 solutions

example 1: A solution is prepared by adding 0.1 Mol of sodium sulfide, Na2S, to 1.00 L of water. The solution is: - basic - neutral - acidic example 2: A solution is prepared by adding 0.1 Mol of lithium nitrate LiNO3, to 1.00 L of water. The solution is: - basic - neutral - acidic

pH of buffer solution

Hydrofluoric acid (HF) has an equilibrium constant Ka value of 7.2 x 10^- 4. Part a: 0.250 mol of F-- ions (in the form of NaF) are added to 1.0 Liters of 0.1 mol L-1 aqueous HF. Calculate the resulting pH? Part b: The solution produced in (part a) is added 10.0 ml of 5.0 mol L-1 NaOH. Calculate the resulting PH?

Disodium edetate

5. 0.1060g of sodium carbonate, dissolved in 20ml of water, was expected to give a titre of approximately 20ml of hydrochloric acid. what would you expect the approximate titre value to be if the carbonate had been dissolved in 40ml of water? 6. 20ml of a 1.103% w/v calcium lactate solution was analysed by titration against d

Moles and Formulas for Solutions

1. In a standarisation of hydrochloric acid solution, 0.1232g of sodium carbonate were used. calculate the number of moles of sodium carbonate used. 2. In a standarisation of hydrochloric acid solution, 0.1099g of sodium carbonate were used. This resulted in a titre value of 25.49ml. calculate the number of moles of hydrochlo

Determine the molar mass.

Acetylsalicylic acid acid is the active ingredient in aspirin. It took 35.17 mL of 0.5065 M sodium hydroxide to react completely with 3.210 g of acetysalicylic acid. Acetylsalicylic acid has only one acidic hydrogen. What is the molar mass of acetylsalicylic acid? I know the answer but I need help to set up the problem and to k

Carbonate chemistry --- Impact of solubility on ability to increase pH?

How does the solubility of a particular reactant affect its ability to raise pH? I am particularly interested in the difference between sodium carbonate and calcium carbonate. Calcium carbonate is much much less soluble than sodium carbonate. However, does the solubility of the carbonate matter when adjusting pH from say

Aluminum sulfate as a flocculant

In a lab experiment, a solution of weak acids in water exhibit a pH of 3.7; the solution is known to have a known quantity of dissolved solids in solution. Paper makers alum (aluminum sulfate = Al2(SO4)3) is supposed to be used to coagulate/flocculate the dissolved solids in order to precipitate those solids. In the course

Carbonate Chemistry

I have a lab experiment in which I have a slurry of wood pulp at a pH of 4.0; I'm asked to use sodium carbonate to raise the pH of the slurry to pH 5.5. I then press the wood slurry to de-water and place it in an oven until it is bone dry. I then take the wood sample out of the oven and place it in a bath of water to determine h

Separation of A Three Component Mixture by Extraction

2. Determine the amount of each component recovered and total their masses. Calculate the % recovery based on your starting mass. Amine with watch glass weighed 18.5197g - 18.4998g = 0.0199g, substance was yellow. Carbonoxylic acid with watch glass weighed 18.7402g - 18.7237g = 0.0165g. 3. Calculate the % composition of the mi

Chemistry Half Reaction Reduction and Oxidation

1. The half reaction of NpO2+ to Np+4 is a. an acid-base reaction b. a redox reaction c. reduction d. oxidation 2. The standard hydrogen electrode has a half-cell potential of 0.00v. This is due to a. arbitrary convention b. hydrogen gas being insoluble in water c. coincidence d.

Multiple chemical reaction questions

1. The following is best described by which type of reaction? CaCO3 --> CaO + CO2 A. decompostion B. acid-base neutralization C. single displacement D. redox E. double-displacement (metathetical) 2. The following best describes which type of reation? 2Ca + O2 --> 2CaO a. decomposition b. acid-base neutraliz

Determine solubility of boric acid (H3BO3) at various pH's

This problem indicates that 1 gram of hydrated boric acid (H3BO3) is added to 1 liter of water at pH 7.0 and at standard temperature. The solubility is stated in the problem as 5.7 grams per 100 ml of solution. A pKa is also given as 9.24. 1) What does the pKa value mean? 2) How would I determine the amount of boric acid

Type of Reaction

What type of reaction does this describe? metal + H2O --> metal oxide + H2 a. decomposition b. acid-base neutralization c. single displacement d. redox e. double-displacement (metathetical).

Solubility of reaction

The Ksp for Fe(OH)2 is 1.8 x 10-11. Will a precipitate form if an 0.4M solution of FeCl2, has its pH raised to 8.3? What is the solubility of Mg+2 in 0.03M HF? Ka for hydrofluoric acid is 6.6 x 10-4. The Ksp for magnesium fluoride is 3.7 x 10-8 Also: Complete the following reactions: a. H2PO4^- +H^+ ->

Vitamin C Content of Juices

Assignment 1 of Procedure 1 1. Calculate the molarity of the freshly-prepared ascorbic acid standard (known strength) solution: (a) Mass of ascorbic acid used:0.05g (b) Moles of ascorbic acid (MW=176.1 g/mol):not sure 0.000284 (c) Total volume of standard solution prepared (mL):100.01mL (d) Asc

Equilibrium Acid-Base Reactions

40.00 mL of an unknown ammonia solution is titrated with 25.0 mL of 0.105M HCl to the equivalence point. The Kb for ammonia is 1.8 x 10-5. What was the concentration of the original ammonia solution? What is the concentration of NH4Cl at the equivalence point? What is the pH at that point?

Equilibrium and Acid - Base Reactions

1. The Ka for HF is 6.6 x 10^-4. What percentage of the HF is ionized if 5 grams are dissolved in 1 liter of water? 2, Assume an indicator, HA, has a Ka od exactly 10^-7. This means that at pH = 7 there are equal numbers of molecules of both colors. What is the ration of colors at pH values of 7.2 and 8.0?

Equilibrium and Acid-Base Reactions

1. The hydration reaction , Na2HPO4 + 2H2O -> Na2HPO4 x 2H2O has a Kp = 6000 at 300K If excess dry, anhydrous Na2HPO4 is added to a 3L container holding 25mmHg of water vapor, what will be the pressure of water after it equilibrates with the sodium phosphate? 2. What is the pH if 2g of NaC2H3O2 and 1g of HC2H3O2 are mixed

Equilibrium and pH compounds

1. Which of the following could NOT be a Bronsted-Lowry base? a. HCO3- b. F- c. SO3-2 d. NH4+ 2. What is the pH of a 0.1M HCl solution? a. 0.1 b. 0 c. 1 d. 10 3. Which is the stronger (more highly ionized) acid? a. HF b. HCl c. HBr d. HI 4. Which of

Calculate the pH for a buffer solution.

Calculate the pH for a buffer solution prepared by mixing 100. mL of 0.60 M NH3 and 200. mL of 0.45 M NH4Cl. The Ka of NH4 + = 5.6 x 10^-10. a) 8.65 b) 9.08 c) 9.87 d) 4.90 e) 6.62

pKb of a Solution of a Weak Base

The pH of a 0.12 M solution of a weak base is 10.30. What is the value of pKb for this weak base? a.) 3.70 b.) 6.48 c.) 10.30 d.) 5.44 e.) 4.49.

The Value of Kb

The value of Kb for methylamine, (CH3)2NH, is 7.4 x 10 ^ -4. What is the pH of a solution containing 0.32 M dimethyl ammonium ion, (CH3)2NH2 + ?

Glucose Synthesis Problems

Glucose is soluble in benzene. If alpha-D-glucose is dissolved in benzene, essentially no alpha-D-glucose is formed. However, if small amounts of phenol and pyridine are added, then the equillibrium amount of alpha-D-glucose is formed but slowly. If, to a solution of alpha-D-glucose in benzene, a small amount of 2-hydroxy-py

Conversion formula between pressure units

What is the formula for converting atm to Torr? example: 1.87 atm to Torr Also what is the formula for converting Torr to mmhg? example: 748 Torr to mmHg What about mb to kPa? example: 998mb to pKa Then in. Hg to atm example:26,88 in Hg to atm

Hydrogen Ion Concentration

How do you find hydrogen ion concentration, and which of the following have the highest concentration? 55.6M H2O 0.25 M HCl 1.0 M CH4 1.2 M NaOh 0.20 M NaH

Acid-Base Equilibria

1. Write formulas for the conjugate bases for each of these acids: a) HCl b) CH4 c) HSO3- d) H2SO4 e) NH3 2. In the following reactions, identify the Lewis acid and the Lewis base: a) Fe3+ + 6H2O ←→ Fe(H2O)36+ b) BF3 + NH3 ←→ F3BNH3 c) BF3 + F- ←→ BF4-

Chemistry Element Questions

1. What is the volume of 1.20 x 1022 molecules of nitric oxide gas, NO, at STP? 2. What is the mass of sodium phosphate (163.94 g/mol) that yields 1.00 g of calcium phosphate (310.18 g/mol) precipitate? __CaCl2(s) + __Na3PO4(aq) → __Ca3(PO4)2(s) + __NaCl(aq) 3. How many moles of calcium metal react to yield 0.50