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Acids and Bases

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?

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?

PH of a solution

40.4mL of 0.100M nitric acid solution is added to a 1.00L volumetric flask and the solution is made up to the mark. What is the pH of the solution?

Calculating the pH of a solution.

What is the new pH if a drop containing 0.001 moles of HCl is added to 100.00 ml of a solution 0.100M in each of acetic acid and sodium acetate? (ka for acetic acid 1.75e-5) 1.75x10^-5

Percent ionization

What is the percent ionization of the acid in a 0.0008M solution of nitrous acid (HNO2) (ka 4.0e-4)? (4 times 10 to the power of -4)

Applied Chemistry Problems

1) The lead batteries in cares are based on the following pair of half-reactions PbO2 (s) + HSO4- (aq) + 3H+ (aq) + 2e- --> PbSo4 (s) + 2H2o (l); E=1.63V PbSO4(s) + H+ (aq) + 2e- ---> Pb(s) + HSO4- (aq); E= -0.293V a) Write the balanced cell reaction that occurs when a lead battery generates current. b) Write the

Strong and Weak Acids

What is the difference between a strong acid and a weak acid? Give one example of each. What is meant by the ionic product for water, Kw? Define pH and hence calculate the pH of a solution of a) 0.01 M hydrochloric acid b) 0.1 M sodium hydroxide c) 0.2 M sulphuric acid d) 0.1 M butanoic acid, given that Ka = 1.51 x 10-5

Determining the pH of an aqueous solution

Determine the pH of an aqueous solution prepared by mixing 50 mL of .125 M KOH with 50 mL of .125 M HCl while maintaining the temperature of the the system at 50 degrees C.