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Acids and Bases

Calculate the molarity and pH of the solution

Mass of solute is given followed by the total volume of solution prepared. Calculate the molarity. a. 1.37 g of NaOH; 125 ml b. 4.29 g of Kl; 250. ml c. 2.95 mg of Pb(NO3)2; 4.95 ml d. 0.997 kg of NaNO3; 125 L What mass of the indicated solute does each of the following solutions contain. a. 2.50 L of 13.1 M HCl solutio

Zinc Borate in Treatment of Wastewater

Can you please take a look at the attached and give me some feedback. I want to understand why specifically pH is driven way low and then way high to promote precipitation of the zinc solids. Please take a look and comment. In our process, zinc borate (2ZnO-3H3BO3-3H2O) ultimately splits and dissociates to zinc oxide and b

Solubility of Zinc Oxide, Boric Acid, and Aluminum Sulfate

Hope you can help....I've always struggled calculating solubilities of compounds at different pH's. I have 3 separate but related questions: 1) 1000 g of zinc oxide is added to a 1 liter container of pH neutral water (pH 7.0); the solubility of the ZnO is given as .29 g/L at pH 7.0; how much more ZnO would dissolve if the pH

Separating Sodium Carbonate, Chloride and Sulphate

Assuming an imaginary mixture of sodium chloride, sodium carbonate and sodium sulphate I need to know what test to use to 1st confirm the the compostion and 2nd to find the percentage composition mixture. I need to know which test would be useful and the calaulations needed so I can preform the in the lab.

'What Salt will Form', Precipitation and Reaction Type Problems

When each of the following strong acid/strong base reactions take place. What salt would form with these and how would you find out. HCl (aq) + KOH (aq) --> RbOH (aq) + HNO (aq) --> HClO4 (aq) + NaOH (aq) --> HBr (aq) + CsOH (aq) --> How to Balance the following equations that describe combustion reactions. C2H6 (

Determine the molar mass of an unknown acid.

Please see attached file for full problem description. 1. Determine the molar mass of an unknown acid. Called the unknown acid HX, and it reacts with NaOH. Equation is: NaOH(aq)+HX(aq) --> NaX(aq)+H2O(l) 1 mole of NaOH reacts with 1 mole of HX. Weighed a sample of HX is titrated with standard NaOH. Weigh the vial contai

Prediction of Changes to DeltaG in a Non-Standard Cell

-438 kJ/mol is the free energy change of lactate oxidation by Fe3+ under non-standard conditions assuming that: C3H5O3- + 12 Fe3+ + 3 H2O -----> 3 CO2 + 11 H+ + 12 Fe2+ [Fe2+]=10^-4 M pH=7 T=25 degree centigrade [lactate]=10^-3 M Carbon dioxide is in equilibrium with atmospheric CO2 Fe3+ is in equilibrium with

A Selection of Net Ionic Equation from Reaction Problems

Can you please assist me in understanding what the name of the products and the net ionic equations are for the following mixtures? -ammonia poured into aluminum nitrate -barium chloride poured into sodium sulfate -copper(II) chloride poured into sodium carbonate -lead(II) nitrate poured into potassium iodide -m

Products and Equilibria of Reaction of Alum with Carbonates

If we were to add sodium carbonate and calcium carbonate to separate samples of Al2(SO4)3, what would the reaction/equilibrium equations look like? What are the pKa values of Na2SO4 and CaSO4 ---- even though they are salts, would they continue to add at least in part to the acidity of the solution?

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

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

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

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

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

Acid-Base Calculations

1.) Calculate the four values of pH, pOH, [H+], and [OH-] for a 0.100 M of HCl. 2.) Calculate the four values of pH, pOH, [H+], and [OH-] for a 0.00250 M NaOH solution. 3.) Calculate the four values of pH, pOH, [H+], and [OH-] fo a 0.00150 solution of nitric acid (HNO3). 4.) The Ka of HCl is known to be about 10^7. What is th

Mole, Mass, Enthalpy, and Energy Change Problems

See attached file for full problem description. 1. Which is not a solution? brass, fog, hydrochloric acid, or wine 2. How Many Moles of CuO can be produced from 0.0450 mol if Cu2O in the following reaction? 2 Cu2O(s) + O2(g) -> 4 CuO(s). 3. Methane and Oxygen react to form carbon dioxide and water. What mass of wa