1. How many grams of dry NH4Cl need to be added to 2.40 L of a 0.200 M solution of ammonia, NH3, to prepare buffer solution that has a pH of 8.83? Kb for ammonia is 1.8×10-5.
2. A beaker with 115 mL of an acetic acid buffer with a pH of 5.000 is sitting on a benchtop. The total molarity of acid and conjugate base in this buffer is 0.100 M
A student adds 4.20 mL of a 0.490 M HCl solution to the beaker. How much will the pH change? The pKa of acetic acid is 4.740.
3. Calculate the molar solubility of SrF2 in the following substances.
1.5×10-2 M Sr(NO3)2
1.3×10-2 M NaF
4.There is a solution that is 3.5×10-2 M
in HCN (Ka=4.9×10-10) and 1.0×10-2 M in NaCN.
Calculate the percent dissociation of HCN in this solution.