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Acids and Bases

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?

AP Problem

Methylamine, CH3NH2, is a weak base that reacts according to the equation CH2NH2 + H2O <--> CH3NH3^1+ + OH^1-. The value of the ionization constant, Kb, is 5,25 x 10^-4. Methylamine forms salts such as methylammonium nitrate, (CH3NH3^1+)(NO3^1-). (b) Calculate the pH of a solution maded by adding 0.0100 mole of a solid methyl

Molarity of a solution - NaOH

A 0.345 gram sample of oxalic acid dihydrate crystals (H_2 C_2 0_4 - 2 H_2 0) is dissolved in water and titrated with 24.5 mL of a sodium hydroxide solution. What is the molarity of the NaOH?

A study of pH - lab related

1. 10.00 mL of 0.1000 M NH3 was diluted with distilled water to 40.00 mL. Calculate the pH of the dilute solution. (Kb NH3 = 1.8*10^-5) 2. The dilute solution was titrated with 0.0500 M HCl. Write the equation for the reaction between ammonia and hydrochloric acid. Calculate the pH of the solution after adding 4.00 mL

Cell Potential

Calculate the standard cell potential for each of the following electrochemical reactions: a) the reduction of Sn(IV) to Sn(II) by Zn(s) b) the oxidation of Sn(II) to Sn(IV) by dichromate ion in acid solution c) the reduction of NO3- (negative sign there is superscript) to NO by cobalt metal

Solving for pH

I have .20M of a solution NaCN. Ka for HCN = 4.0 x10 10. How do I solve for pH?

Solving for Kw

I have the following data: Kw = 5.47x10 -14th temperature = 50 degrees celcius [H3O+] = x pH = x How do I find the value for [H3O+] and how do I find the value for pH?

Molar and Concentration

If 4.oo mL of 0.0250 M CuSO4 is diluted to 10.0 mL with pure water, what is the molar concentration of copper (II) sulfate in the dilute solution? ______________________________ molar A 10.0-mL sample of 2.56 M HCL is diluted with water to 250. mL. What is the concentration of HCl in the diluted solution? Concentr

If more concentrated NaOH is used during standardization would the pKa change?

Benzoic acid is an organic acid with a Ka of 6.5x10^-5. It can also be used as a primary standard like KHP. If benzoic acid were used to standardize NaOH, determine if if the equivalence point is acid, basic, or neutral based on the following criteria?: pKa < 0 is strong acid 1<pKa< 10 weak acid pKa > 10 very weak I

Aqeous solution, oxidizing agent

37) Which the following aqueous solutions has the highest boiling point? a) 0.10 M potassium sulfate b) 0.10 M HCl acid c) 0.10 M ammonium nitrate d) 0.10 M magnesium sulfate e) 0.20 M sucrose 38) When 70 ml of 3.0 M Nasub2COsub3 is added to 30 ml of 0.1 M NaHCOsub3, the resulting concentration of Na+ is? 39) Which of

Which if any of the following species...

35) which if any of the following species are in the greatest c in a 0.100 molar solution Hsub2SOsub4 in water? a) Hsub2SOsub4 molecules b) Hsub3O^+ ions c) HSOsub4^- ions d) SOsub4^2- ions e) all species are in equillibrium and thus the same concentration. 36) at 20 degrees C the vapor pressure of toluene is 22mm Hg

Standard Heat of Formation - Acid/Base

CHsub4(g) + 2Osub2(g) --> COsub2(g) + 2Hsub2O(l) triangleHsub f^degree symbol Hsub2O(l) =-285.8kJ/mole triangleHsub f^degree symbol COHsub2(g) =-393.3kJ/mole 1) What is the standard heat of formation, triangleHsubf^degree symbol, of methane, CHsub4(g) as calculated from the data above? 2) each of the following can act as

Oxidation

Questions 17 - 18: Hsub3AsOsub4 + 3I^- + 2Hsub3O^+ -> Hsub3AsOsub3 + Isub3^- + 3Hsub2O The oxidation of iodide ions by arsenic acid in acidic aqueous solution occured accoring to the balanced equation above. The experimental rate law for the reaction at 25 degree C is: 17) What is the order of the reaction with respect t

Elements

Questions 4 - 6: a) Hydrofluoric acid b) Corbon dioxide c) Aluminum hydroxide d) Ammonia e) hydrogen peroxide 4) Is a good oxidizing agent. Ans A, B, C, D or E 5) Is used extensively for the production of fertilizers. Ans A, B, C, D or E 6) Has atmospheric properties. Ans A, B, C, D or E

Calculating Percent Ionization

Question: A 0.600m aqueous solution of a weak acid HX has a freezing point of -1.28 degrees C. Calculate the % ionization of HX. - Kf H2O= 1.86 - m = molality

Acid, Bases, Equilibria Questions

1) The solvent cation in liquid ethanol, CH3CH2OH, is a) CH3CH2O- b) H+ c) CH3CH2OH+ d) CH3CH2OH2+ e) CH3CH2OH- Answer _________ 2) Fill in the blanks. a) the normality of 0.20M solution of H2SO4 ________________________ b) The following reaction is best classified as an Arrhenius, Br

Assume that Isaac Asimov's figures are correct...

Assume that Isaac Asimov's figures are correct, and that 3.5 X 10 to the 14th power of the 3.0 X 10 to the 26th power carbon atoms in your body are radioactive. Calculate the fraction of carbon atoms that are radioactive carbon-14. Natural sources of radiation account for 82 % of all public exposure while human-made sources a

Acid/Base Chemistry Problems

1. Solve the following problem related to the solubility of equilibria of some metal hydroxides in aqueous solution. a) The solubility of Cu(OH)2 (solid)is 1.72x10^-6 gram per 100 ml of solution at 25 degrees C. i. Write the balanced chemical equation for the dissociation of Cu(OH)2 (solid) in aqueous solution. ii. Calcula

Which one is acidic, basic or neutral?

Will 0.10 M aqueous solutions of the following salts be acidic ("A"), basic ("B") or neutral ("N") (Assume a solution is neutral if its pH is 7.00 plus or minus 0.05). a. disodium hydrogen citrate b. sodium dihydrogen citrate c. sodium sulfate d. ammonium dihydrogen phosphate e. ammonium cyanide f. ammonium hydrosu

Ionization and reactions of acids and bases

1. Write equations for the following: A. Ionization of the strong acid, HBr in water B. Ionization of the weak acid, HNO2 in water. C. Reaction of the weak base (CH3)2NH with water. D. Reaction of the acid, HNO3 with CaCO3 solid. E. Reaction of HCl(aq) with KOH(aq)

Find pH

Could you show me how you solved to get pH of each solution: Solution A has [H3O+] = 7.2à?10-5 Solution B has [H3O+] = 7.2à?10-4 Solution C has [OH-] = 3.0à?10-11 Solution D has [OH-] = 6.5à?10-11 (i) Which solution has the highest pH? (ii) Which solution is the least acidic? (iii) Which solution is the most

Calculating Necessary Tonnes of Lime to Raise a Lake's pH

One of the impacts of fossil fuels is an increase in acid deposition (or acid rain as many people refer to it). The following exercise asks you to calculate how much lime (an alkaline rock, not the tasty green fruit) it would take to increase the pH of a small lake. Consider a small lake in the Adirondack region of New York