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Acids and Bases


Question: 5.0 mL of 12 mol NH3 / Litre solution is added to 500.0 mL of 0.050 mol AgNO3 / Litre solution. Assume the combining volumes are additive, What molar concentration of silver ion will exist in solution after equilibrium is established? Ag+ + 2 NH3 = Ag(NH3)2+ ( Kf for Ag(NH3)2+ is 1.5 x 107 ) P

Mass of potassium hypochlorite

What mass of potassium hypochlorite must be added to 450.0 mL of water to give a solution with pH = 10.20? Please see the attached file for full problem description.

Buffer effective

Over what range of pH is a HOCl - NaOCl buffer most effective? pH 2.0 - pH 4.0 pH 7.5 - pH 9.5 pH 6.5 - pH 8.5 pH 6.5 - pH 9.5 pH 1.0 - pH 14.0

Lab Report: Reaction Order and Rate Laws

Objective: To study the effect of reactant concentration on the rate of the reaction between sodium thiosulfate and hydrochloric acid and to determine the order of each reactant and the rate law for the reaction. 2 HCI(aq) + NaS2O3 (aq) --> S(s) + SO2 (aq) + H2O(l) + 2NaCL(aq) Calculations: (a) Calculate the initial an

Back titration of ammonium chloride

In a labratory. A solution of Ammonium chloride was given, for us to find the concentration by techniques of back titration. NaOH was added to the diluted ammonium chloride and heated. Then Titrated with HCL adding few drops of bromocresol green indicator. Colour turned yellow. What does this mean? I have done the calculation.

Empirical Formula of the Compound

A compound of iron and oxygen is found to have a mass of 6.13 grams. If the mass of iron is determined to be 4.29 grams, what is the empirical formula of the compound? Please give step by step answer in simplest way to do not making it complicated. Show all steps and solution please.... (See attachment for rest of question

MOLARITY of Sodium hydroxide solution

Sodium hydroxide is used extensively in acid-base titrations because it is a strong, inexpensive base. A sodium hydroxide solution was standardized by titrating 28.71 mL of 0.1822 M standard hydrochloric acid. The initial buret reading of the sodium hydroxide was 2.70 mL and the final reading was 30.33 mL. What was the molarity

Solving for the pH of a Compound

Question: What is the pH of 0.097 M of triethylammonium chloride (CH3CH2)3 NHCL? I know that in order to solve this i need to find the Kb, which is equal to Kw/Ka, I know that Kw = 1E-14, but I do not know which Ka to use? Once i know the Kb, i will be able to solve this problem and find the pH, i just need help finding the a

Equilibrium vapor pressures

Compare the vapor pressures of methanol,ethanol,acetic acid, water, and benzene. Which compund appears to have the strongest intermolecular forces at 100C If one compound has a higher equilibrium vapr pressure than another at a particular temperature, will it necessarily have a higher equilibrium vapor pressure at all tempe

Solutions, Acids, Bases Molarity of a Solution

1. 0.54 g of ammononium chlordie is dissolc=ved in 250 mL of solution. Calculate the molarity. 2. What volumne of solution would be required to deliver 6.84 g og 0.200 M aluminum sulfate solution? 3. Calculate the molarity of a solution if 126 mL of 6.25 M NaOH was diluted to a total volume of 250mL. 4. Calculate the pH

The pH level for saturated water

I need to see how the following is done. Calculate the pH of CO2-saturated water at 25 degrees C, given that the CO2 concentration in air is 320 and that, for carbon dioxide, the Henry's Law constant KH=3.4E-2 mol L-1 atm-1is at 25 degrees Celsius. Furthermore, the ionization constant, Ka, for H2CO3 has a value of 4.5E-7 mol

Strong Acid & Bases NMR

a. There are only four lines in the aromatic region of the fully 1H decoupled 13C NMR spectrum of propyl p-tolyl ether (110-160 ppm), yet there six aromatic carbon atoms. Explain. b. Which is a stronger base, aniline or cyclohexylamine? Explain. c. Write an equation for the reaction of pthalimide with potassium amide (a str

pH Calculations for Acids

103897 okay if expalin math Only for above listed OTA-ONLY. All others called in. Please EXPLAIN the math. 100 mL of a 0.1 M NaOH solution is being titrated with 0.2 M HCl solution. a) What is the pH of the solution after 25 mL of the HCl solution has been added? b) What is the solution after an additional 20 mL of HCl solut

Acid Base Equilibria

Please show all work and remember this is a first year course. Chem is my weakest subject. Please send responsse in Word. Also, if you are not willing to show me the proper way to do these by showing the calculations and will only supply me with some notes tht I could read out of any textbook myself, please do not take th

Lowest Concentration of Salt in Water

Everything is already answered I just need to know if I am on the right track, please help I am really struggling with chemistry and I absolutely need to know how to do these problems correctly, so if I am wrong can you please tell me were my error is. ----------- Which of the following salts would give you the lowest co

Conjugate Acid-Base Pairs

1. Conjugate Acid-Base Pairs. Identify the conjugate acid-base pairs in each of the following reactions. Label each species as an acid or a base. a. NH4+(aq) + CN-(aq) --> NH3(aq) + HCN(aq) b. CH3COOH(aq) + F-(aq) --> CH3COO-(aq) + HF(aq) c. HPO42-(aq) + H2O(l) --> H2PO4-(aq) + OH-(aq) d. NH3(aq) + SO4 2-(aq) --> N

The dissolution of a solid in water

I) At 25ºC, 0.212g of barium hydroxide is dissolved completely in sufficient water to make 0.25 liter of final solution. What is the hydroxide ion concentration in mol litre-1? Given answer in scientific notation to an appropriate number of significant figures. ii) What assumption must you make in order to carry out the cal

Acid-Base Equilibrium

A solution is prepared by mixing 46.8 mL of 0.16 M Pb(NO3)2 with 75.3 mL of 1.4 M KCl. Calculate the concentrations of Pb2+ and Cl- at equilibrium. Ksp for PbCl2(s) is 1.6 10-5.

Ion concentration and pH of solution

At 25 degrees C, 0.212 g of barium hydroxide is dissolved completely in sufficient water to make 0.25 liter of final solution. What is the hydrogen ion concentration (in mol/liter) in this solution? What is the pH of this solution (to the nearest integer)

Arranging half-cell reactions in order

Arrange the following five reduction half-cell reactions in order listing the largest positive reduction potential first and give the best oxidizing and reducing agents. Observations: i) A reacts spontaneously with 1 mol/L BNO3, 1 mol/L D(NO3) and dilute sulfuric acid. A does not react 1 mol/L C (NO3) ii) B does not re

pH of a Buffer Solution and After Dilation

When microorganisms reproduce they release waste products that may change the pH and prevent further reproduction. Therefore culture mediums for growing microorganisms are usually buffered. The median for the culture of lactobacilli includes a buffer prepared by dissolving 25 grams K2HPO4 and 25 grams KH2PO4 in water and dilut

Hydrogen selenide production

See attached Hydrogen selenide can be prepared by the reaction of aluminium selenide with water, the other product being solid aluminium hydroxide, Al(OH)3. At STP hydrogen selenide gas has a density of 3.61g litre -1. Draw a diagram of how to prepare a jar of dry hydrogen selenide, from the reaction between aluminium sel

Dry Hydrogen Selenide

a) Write a balanced equation for the reaction of aluminium selenide with water to Hydrogen selenide and solid aluminium hydroxide (including physical states) showing the sequence of partially balanced equations needed, including a brief description of the strategy used. b) The density of hydrogen selenide at STP is 3.61 g lit

Percent disagreement and avogrado's number

How do you calculate the percent disagreement using a calculator for 1.01x10^19 (Avogrado's number of oleic acid molecules /mol (theoretical result being Avogrado's number)? Please be specific because I am not quite sure how to do this on the calculator.

PH and precipitation

A 0.10 M Mn 2+ solution is saturated with H2S. At what pH will MnS begin to precipitate? [H2S] sat'd=0.10M

Equilibrium and PH

A phosphate buffer consisting of H2PO4(-1) and HPO4(-2) helps control the PH of physiological fluids. Many carbonated soft drinks also use this buffer system. What is the PH of a soft drink in which the major buffer is 0.153 M NaH2PO4 and .158 M Na2HPO4?