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Acids and Bases

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

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)

Half life of a reaction

Sucrose decomposes in acid solution, according to the first order rate law, to give Glucose and fructose. If the half life for the reaction is 3.33 hours at 25 degree celcius, what fraction of a sample of sucrose would remain after 9 hours ?

Solution Reactions

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?

Acid Strength

The pH of 0.500M ammonium chloride, NH4Cl, is 4.78. What is the value Ka for this acid?