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Acids and Bases

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.

Understanding acid-base chemistry.

Amide ion (H<sub>2</sub>N-) is a stronger base than the hydroxide ion (OH-). Which would you expect to be a stronger acid, NH<sub>3</sub> or H<sub>2</sub>O? Why?

Understanding acid strength, pKa.

Picric acid (C<sub>6</sub>H<sub>3</sub>N<sub>3</sub>O<sub>7</sub>) has a pKa of 0.3. Formic acid (CHO<sub>2</sub>H) has a pKa of 3.7. Which is the stronger acid?

Understanding buffers and weak acids.

Ascorbic acid (vitamin C) has a pKa of 4.2 at 24 degrees Celsius. State the pH of the solution when the ratio of unprotonated to protonated forms of ascorbic acid is (a) 1:1 (b) 1:10 (c) 10:1 (d) 1:3 (e) Which form of ascorbic acid predominates at physiological pH?