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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

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

Solving for pH

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

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

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

Chemistry applied practical situations - pH of soil

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

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

PH calculations

Calculate the pH with the correct significant figures of: a. A solution prepared by dissolving 2.55g (NH4)2SO4 (FW=132.141;Ka of NH4 = 5.7x10^-10)in 100.0 ml of water, adding 100 ml of 0.201 M NaOH, and diluting to 500.0 ml with water. b. H2C, is a weak diprotic acid with a Ka1=1.2X10^-3 and Ka2 = 8.9x10^-9. A 30.00 ml

Determine minimum pH for precipitate formation

What is the minimum pH at which aluminum hydroxide, Al(OH)3 will precipitate from a 0.020 M Al(NO3)3 solution. Consider activity effects. The Ksp for Al(OH)3 is 3x10^(-34). Assume the pH can be changed without increasing the solution volume.

Calculating Mass

Sodium chloride is obtained when sodium carbonates react with hydrochloric acid. The equation for the reaction is: Na2CO3 = 2HCl --> 2NaCl + CO2 + H20 Calculate the mass of sodium chloride that can be obtained when 5 g of sodium carbonate is completely decomposed. (RAM = C=12, 0 = 16, Na = 23)

Solution Reactions of Strong Electrolytes

1. Identify each of the following substances as strong electrolyte, weak electrolyte, or nonelectrolyte: Ba(NO_3)_2 Ne NH_3 NaOH. 2. Predict and explain which of the following systems are electrically conducting: solid NaCl molten NaCl an aqueous solution of NaCl. 3. Characterize the following compounds as solu

Multiple choice questions about buffering solutions.

Which of the following solutions is not a buffer? a. 125mL of 0.200M HCl added to 200mL of 0.400M CH3CO2- b. 200mL of 0.400M HCl added to 125mL of 0.200M CH3CO2- c. 200mL of 0.500M NaOH added to 200mL of 1.000M HF d. 100mL of 0.500M H2PO4- added to 100mL of 0.100M HPO42- e. 100mL of 0.200M HF added to 300mL o

Ksp---2 Problems

1.) A saturated solution of calcium sulfate can be prepared by diluting 0.29g of CaSC4 to 250mL. what is the Ksp of calcium sulfate? 2.) At pH 10.0, only 0.019g of MgCl2 will dissolve per 1L of solution. What is the Ksp of magnesium hydroxide, Mg(OH)2?

Finding the pKa of a weak acid.

A buffer is prepared by adding 1.50x10(exponent 2)mL of 0.250M NaOH to 2.50x10(exponent 2)mL of 0.350M weak acid, HB. The solution is diluted to 1.00L. If the pH of the resulting solution is 5.55, what is the pKa of the weak acid?

Calculating the pH of a solution.

25.00ml of a 0.200M nitric acid solution is added to 50.00ml of a 0.100 M sodium hydroxide solution. What is the pH of the solution?