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Acids and Bases

Oximes for Crystalline Materials

Oximes are usually crystalline materials and have been prepared as a means of identifying liquid ketones or aldehydes. It has been found in the preparation of these derivatives that if the concentration is too high (low pH), that the oxime does not form. Explain.

Calculate the pH of CO2-saturated water at 25 degrees C

Calculate the pH of CO2-saturated water at 25 degrees C, given that the CO2 concentration in air is 343 and that for carbon dioxide the Henry's Law constant KH=3.4E-2 mol L-1 atm-1 at 25 degrees C. Furthermore, the ionization constant, Ka, for H2CO3 has a value of 4.5E-7 mol L-1 at this temperature.

Formal Charges and Resonance: Example Questions

For a molecule of fluorous acid, the atoms are arranged as HOFO. What is the formal charge on each of the atoms? Enter the formal charges in the same order as the atoms are listed. Two possible electron-dot structures are shown for the cyanate ion,NCO- . What can you conclude about how favorable the structures are? a) Str

Preparation of an IV Solution

I need help preparing an IV solution. I have all the ingredients below in solid form, and plenty of sterile distilled water. I need to prepare a solution so that each liter contains the following ingredients at the following concentrations. 0.03 M Galactose 40 millimoles Fructose 50 milliev. lactose 0.008 M Magnesium Phosp

Resonance of Conjugate Base and Bases: Example Problems

1. Draw all relevant resonance structures for the conjugate base or base. 2. Predict where the 3 compounds would be relative to this order. 3. Explain your reasoning for your predictions. I have attache the structures and the questions. Thanks

Net ionic equation

Solid magnesium carbonate reacts with an aqueous solution of perchloric acid what is the net ionic equation for the below balanced equation? MgCO3(s)+2HClO4(aq)>>Mg(ClO4)2(aq)+H2O(l)+CO2(g)

Acid oxide and basic oxide

1. Provide two examples each of an acidic oxide and a basic oxide. For each example (four in all) write a balanced reaction equation with water to support your claim. a. Acidic oxide 1 Reaction with water b. Acidic oxide 2 Reaction with water c. Basic oxide 1 Reaction with water d. Basic oxide 2 Reaction with wate

PH of buffer system

Calculate the pH of the 0.32 M NH3/0.35 M NH4Cl buffer system. I think i was near the right anwser with 4.71 but this was wrong. Should i assume that the buffer system is in equlibrium at 80 mL? What is the pH after the addition of 20.0 mL of 0.050 M NaOH to 80.0 mL of the buffer solution?

PH at eqivilance point

Calculate the pH at the equivalence point in the titration of 66 mL of 0.10 M methylamine with a 0.20 M HCl solution. i found the kb of Methylamine to be 4.4 X 10^-4. but you use the ka of CH3NH3+ which is 2.3 X 10^-11. I thought it should be 10.94 but its incorrect.

Chemistry Sample Solution: pH of Titrated Solution

Exactly 100 mL of 0.20 M nitrous acid (HNO2) are titrated with a 0.20 M NaOH solution. Calculate the pH for the following. (a) the initial solution 2.02 is correct (b) the point at which 80 mL of the base has been added 2.44 is incorrect and differs from the correct answer by 10% to 100%. (c) the equivalence point

PH of a buffer system

(a) Calculate the pH of the 0.20 M NH3/0.18 M NH4Cl buffer. for this part i got the wrong anwser of 9.21 so im not sure how to even begin part b (b) What is the pH of the buffer after the addition of 10.0 mL of 0.10 M HCl to 70.0 mL of the buffer?

Lab

Lab: Standardization of NaOH Solution Procedure !: 1. Prepare the NaOH solution by dissolving approximately 4g of solid NaOH in 200mL of water in a 250mL beaker. Calculate the approximate NaOH concentration: a. Convert grams of NaOH to moles of NaOH (MW = 40.00, moles = g/MW) b

Trifluoromethane Sulfonic Acid

What is the pH of 380.0 mL of an aqueous solution containing 0.523 g of the strong acid trifluoromethane sulfonic acid (CF3SO3H)? I dont know how to find the Ka of sulfonic acid or do I even need it to solve for the pH?

KHSO4 Solution

What are the concentrations of HSO4-, SO42-, and H+ in a 0.35 M KHSO4 solution? (Hint: H2SO4 is a strong acid; Ka for HSO4- = 1.3 10-2.) I've tried .085 for HSO4- and .054 for H+.... what am i doing wrong? Im getting confused because the tables in my chem book dont have a Ka value for KHSO4

Chemistry: Stoichiometric sample calculations

Hydrofluoric acid,HF (aq) , cannot be stored in glass bottles because compounds called silicates in the glass are attacked by the HF (aq) . Sodium silicate (Na2SiO3), for example, reacts as follows: Na2SiO3(s)+8HF(aq)>>H2SiF6(aq)+2NaF(aq) - How many moles of HF are needed to react with 0.330 mol of Na2SiO3? - How many

Calculating the Ka for monoprotic acid

A 0.040 M solution of a monoprotic acid is 14 percent ionized. Calculate the ionization constant of the acid. How do I integrate these two equations to solve this problem? percent ionizations = ionized acid concentration @ equilibrium/initial concentration of acid & Ka= ([H3O+][A-])/[HA]

What are the subscripts in the actual molecular formula

The empirical formula is CH2O the compound is 40% C, 6.70%H and 53.3% O and assume we have a 100g sample of it. question: the molecular formula mass of this compound is 90.0 amu. What are the subscripts in the actual molecular formula?

Lab

Chemistry Lab Procedure: 1. Take a burette from the glassware shelf and place it on the workbench. 2. Fill the burette with 50mL of 0.2M potassium permanganate solution. Record concentration. 3. Take flask and add 10mL of New hydrogen peroxide (New H2O2). 4

Solving Example Equilibium Equations

In order to do the following problem, do I subtract the Kc from each other? The following equilibrium constants have been determined for hydrosulfuric acid at 25°C. H2S(aq) = H+(aq) + HS -(aq) K'c = 9.5 10-8 HS -(aq) = H+(aq) + S2-(aq) K"c = 1.0 10-19 Calculate the equilibrium constant for the following react

PH, OH, POH

How do I complete this table? Sodium hydroxide H = 4.2 x 10^-10 OH = _______ pH = _______ pOH= ________ Hydrocloric Acid H = _________ OH = _______ pH = _______ pOH= 11.5 Potassium Hydroxide H = _________ OH = _______ pH = _______ pOH= 2.5 Acetic Acid ka=1.8 x 10^-5 H = _________ OH = 6.3 x 10^

Solving a Rate Constant Problem

Practice Exercise 13.9 The first-order rate constant for the reaction of methyl chloride (CH3Cl) with water to produce methanol (CH3OH) and hydrochloric acid (HCl) is 3.32 10-10s-1 at 25°C. Calculate the rate constant at 33°C if the activation energy is 116 kJ/mol. My answer, which was incorrect was 3.17e-10. I used th

Treatment for Antifreeze: Administering Ethanol

Treatment for antifreeze poisoning or methanol poisoning generally includes administering ethanol. Why is this effective in combating poisoning by either of these molecules? What is it about methanol and antifreeze that makes it toxic to animals?

Constant-Pressure Conditions of Hydrogen Gas

I'm reviewing for my Chem final and need stuff explained. Please give very in-depth explanations and answers so I can understand how to do it. At 46 degrees C a sample of ammonia gas exerts a pressure of 5.3 atm. What is the pressure when the volume of the gas is reduced to on tenth (0.10) of the original value at the same

Questions I am iffy on

I am completing this class now, reviewing the entire scope of classwork leading to the finals, and there are some review questions I am just real shaky on-and some I simply cannot find an applicable formula for. Thank you! 1. The measured voltage of a cell in which the following reaction occurs is 0.96 V: H2(g, 1.0 atm

Solution Properties Examined

Chapter 13 Practice 7. By referring to the figure , determine the mass of each of the following salts required to form a saturated solution in 350 of water at 30 : , , 10. Calculate the mass percentage of in a solution containing 10.8 in 481 water. 13. An ore contains 2.88 of silver pe

Weak Acids and Buffer Solutions

Could you please show me in detail how to do this? 1. Choose an appropriate weak acid from the list below to make 0.25 liter of a 0.1M buffer solution that has a pH of 4.7: AVAILABLE WEAK ACIDS: Acetic acid (Ka = 1.8 x 10⁻⁵) Citric acid (Ka = 8.4 x 10⁻⁴) Benzoic acid (Ka =

Using activities to calculate pH

What is the final pH of a solution that originally consists of 30.0 mL of a citric acid buffer at a pH of 3.26 and an acid concentration of 6.67x10-2 M after 10.0 mL of 0.0750 M HBr is added? The pKa for citric acid is 3.13. Using activities, find the pH of a solution of 0.0167 M Na2SO4 saturated with Mn(OH)2 (Ksp = 2.0×10-