Which of the following solutions result in a buffer ?

Question

a) 0.050 L of 0.250 M CH3COOH + 0.100 L of 0.250 M NaOH


b) 0.050 L of 0.250 M CH3COOH + 0.100 L of 0.250 M HCl


c) 0.050 L of 0.250 M CH3COONa + 0.100 L of 0.250 M HCl


d) 0.100 L of 0.250 M CH3COONa + 0.050 L of 0.250 M HCl


You must enter all true statements in one continous alphabetical group, no spaces between the letters you enter.

Answer 1

d only - in all the others the HCl or NaOH is in excess.