A 0.012-mol sample of Na2SO4 is added to 400 mL of each of two ...

[imowrer]

A 0.012-mol sample of Na₂SO₄ is added to 400 mL of each of two solutions. One solution contains 1.5  10³ M BaCl₂; the other contains 1.5  10³ M CaCl₂. Given that K_sp for BaSO₄ = 1.5  10⁹ and K_sp for CaSO₄ = 6.1  10⁵:
   
  a.
  BaSO₄ would precipitate but CaSO₄ would not.
   
  b.
  CaSO₄ would precipitate but BaSO₄ would not.
   
  c.
  Both BaSO₄ and CaSO₄ would precipitate.
   
  d.
  Neither BaSO₄ nor CaSO₄ would precipitate.
   
  e.
  Not enough information is given to determine if precipitation would occur.

Question 2

Sodium chloride is added slowly to a solution that is 0.010 M in Cu⁺, Ag⁺, and Au⁺. The K_sp values for the chloride salts are 1.9  10⁷, 1.6  10¹⁰, and 2.0  10¹³, respectively. Which compound will precipitate first?
   
  a.
  CuCl
   
  b.
  AgCl
   
  c.
  AuCl
   
  d.
  All will precipitate at the same time.
   
  e.
  Cannot be determined.

Question 3

The K_sp for Mn(OH)₂ is 2.0  10¹³. At what pH will Mn(OH)₂ begin to precipitate from a solution in which the initial concentration of Mn²⁺ is 0.10 M?
   
  a.
  6.47
   
  b.
  13.3
   
  c.
  5.85
   
  d.
  7.03
   
  e.
  8.15

Question 4

The K_sp for BaF₂ is 2.4  10⁵. When 10 mL of 0.01 M NaF is mixed with 10 mL of 0.01 M BaNO₃, will a precipitate form?
   
  a.
  No, because Q is 1  10¹² and since it is less than K_sp no precipitate will form.
   
  b.
  Yes, because Q is 1  10¹² and since it is less than K_sp a precipitate will form.
   
  c.
  No, because Q is 1.25  10⁷ and since it is less than K_sp no precipitate will form.
   
  d.
  Yes, because Q is 1.25  10⁷ and since it is less than K_sp a precipitate will form.
   
  e.
  None of the above.

[macmac]

Answer to Question 1

a

Answer to Question 2

c

Answer to Question 3

e

Answer to Question 4

c

[imowrer]

Thank you!

[macmac]

Always glad to help...