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Acids and Bases

Freezing Point

How many grams of naphthalene, C10H8, would you add to 49.5 g of benzene, C6H6 (l), to produce a solution that has the same freezing point as pure water? (Use the data from the table as needed.) Molal Freezing Point Depression and Molal Boiling Point Elevation Constants: Solvent Normal Freezing K(fr) Normal

Calculations with Acids and Bases

I) Which one of these is the solute and which one is the solvent in a solution composed of i) 25.0 g of silver in 5.0 g of mercury, and ii) 3.0 g of iodine (I2) in 100.0 mL of ethanol? ii) What is it that makes water such a good solvent for polar substances? Why is it called the universal solvent? iii) What is the mass pe

Determining molar concentration of a compound when pH is known?

Dr M We start with a 1 liter solution of water and a mild acid --- the pH of this solution is 4.0; To this solution, we add 100 grams of Chemical A that has a pH of 10.89 and a molecular weight of 300 g/mol; We then add 110 grams of Chemical B ---- Chemical B has a pH of 8.5 but its mol. wgt is unknown? We then add p

Final pH of a Mixture of Acetic Acid, Alum, and NaOH

A 1 liter solution of a mild acetic acid and water exhibits a pH of 4.0 --- the molar concentration of the acetic acid is unknown but is presumed to be 1x10^-4M; to this solution is added 100 grams of NaOH that has a pH of 12.0; then, 51 grams of aluminum sulfate hydrate (Al2(SO4)3-14H2O) with a pH of 3.5 is added to the solutio

In this continuous process, "phosphoric acid and ammonia are mixed, and a non-hazardous product, diammonium phosphate (DAP) results if the reaction of ammonia is complete.

Attached is a very simple process flow diagram. In this continuous process, "phosphoric acid and ammonia are mixed, and a non-hazardous product, diammonium phosphate (DAP) results if the reaction of ammonia is complete. If the proportion of phosphoric acid is reduced, the reaction is incomplete, and ammonia is evolved. Reduction

Algal Bloom and Changes in pH

Following an algal bloom, the pH of a lake increases from 7.3 to 10. If the pH is due to an increase in OH- ions via the reaction: HCO3 --> OH- + CO2, how many moles of OH- were released to raise the pH to 10?

Strength of Acids

Strength of acids makes a big difference on whether it is a mere sting or the dissolution of your cells. Would you rather have 1 mM of HCl on your skin or 0.1 M of HCl on your skin?

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 and Testing 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.

25 MC Problems : Oxidation Numbers, Nomenclature and General Chemistry

Question 1 (4 points) In which one of the following is the oxidation state of the underlined metal incorrect? Complex Species Oxidation State of Underlined Metal a.[Cr(OH2)3Br3] +3 b.[Co(OH2)6](NO3)2 +2 c.[Co(NH3)2(en)(Cl)2]2SO4 +1 d.[Fe(CO)5] 0 e.[Cr(NH3)6]2[NiCl4]3 +2 Save answer Bottom of Form Question 2 (4 points)

'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

Acid Strength, Base Strength and Anion Stability (16 Problems)

2. Select the strongest base: a. OH- b. SH - c. NH2 - d. Cl- e. CH3CH2 - 3. Consider the following acid-based reaction. Equilibrium for this reaction lies on the: (see attachment for equation) a. Left b. Right c. It cannot be determined 4. Rank the following compounds in order of increasing acidity: 1. BrCH2OH

Balanced Reaction Equations

1. Write the balanced equation for the first step in the reaction between vinegar and baking soda, with carbonic acid (H2CO3) as a product. What type of reaction is this? 2. Write the balanced equation for the second step in the reaction, the liberation of carbon dioxide from carbonic acid. What type of reaction is this? 3

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

CHM - 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

3 Chemistry Multiple Choice Questions

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.