Quiz 3/29

Mg3PO4 (s) = 3Mg^2+ (aq) + PO4^3- (aq)

Equation for dissolving Mg3PO4 (s)

Q = ksp

Give the equation for a saturated solution comparing Q with ksp

Q > ksp

Give the equation for a supersaturated solution comparing Q with ksp

Q < ksp

Give the equation for an unsaturated solution comparing Q with ksp

HCHO2 > NaCHO2

If the pka of HCHO2 is 3.74 and the pH of an HCHO2/NaCHO2 solution is 3.11, what is true?

Highest

The _________ ksp has the highest solubility

True

True or false? A buffer is more resistant to pH change when [acid] = [conjugate base]

It decreases

What is the effect on the concentration of H⁺ in a solution of HCN if KCN is added to the equilibrium solution?

Unsaturated

When Qsp < Ksp

Saturated

When Qsp = Ksp

Precipitate

When Qsp > Ksp

0.20 M NH3 and 0.10 M NH4Cl

Which of the following combinations can be used to make a buffer? (Assume equal volumes are used.) 0.20 M NH3 and 0.20 M HCl 0.20 M NH3 and 0.10 M NH4Cl 0.20 M NH3 and 0.10 M HF 0.10 M NH4Cl and 0.10 M NaF

0.50 M HF and 0.20 M NaF

Which of the following combinations can be used to make a buffer? (Assume equal volumes are used.) 0.50 M HF and 0.20 M NaF 0.50 M HF and 0.50 M NaOH 0.50 M HF and 0.50 M HCl 0.50 M HCl and 0.50 M NaF