Determine whether mixing of the following solutions will or will not produce a buffer solution.
a) Mixing 1L of 0.2 M NaClO4 and 1L of 0.3 M HClO4
b)Mixing 1L of 0.4 M NaF and 1L of 0.3 M HF
c) Mixing 1L of 0.7 M NH4Cl and 1L of 0.6 M HCl
d) Mixing 1L of 0.5 M H2SO4 and 1L of 0.5 M CH3COOH