Question

1. To 1.00 L of 0.0812 molar solution of acetic acid (ionization constant = 1.8 x 10-5 ) few drops of concentrated HCl were added. These few drops contained 0.042 mol of HCl. Calculate the concentration of acetate ions after the addition of HCl. To simplify calculations, neglect the total volume change.

a) 0.20 M b) 2.0 x 10-5 M c) 3.2 x 10-6 M d) None. My value is: ________

2. Write ONLY NET IONIC equations that would occur after the addition of HCl and KOH to the buffer consisting of KClO and HClO in water.

After addition of KOH .............................. After addition of HCl ..............................

3. In the buffer [HClO] = 0.080 M and [ClO-] = 0.020 M. Ka of HClO = 3.0 x 10-8. The pH of the buffer is:

a) 7.52 b) 8.65 c) 7.24 d) None. My value is .........

4. A buffer is 0.025 M in HA and 0.020 M in NaA. Ka = 2.4 x 10-5. What is the expected pH of the buffer after addition of 0.0050 mole of HCl to 1.00 L of the buffer? Neglect the volume change.

a) 4.92 b) 4.25 c) 5.87 d) 4.49 e) None. My value is .........

Answer 1