The ionic strength of a 0.010 M Na3PO4·9H2O aqueous solution is Use tables of activity coefficients in the (lesson or online) to find appropriate values.
M 0.060
M 0.040
M 0.12
M 0.020
Of the following substances, a 0.10 aqueous solution of NH4Cl, Cu(NO3)2, K2CO3, and NaF will form basic solutions.