6.
For a 1.0M solution of each of the following, which has the lowest pH?
a)
[Cr(H
2
O)
6
]
3+
, radius of
Cr
3+
= 69pm (picometers, x 10
-12
m)
b)
[Fe(H
2
O)
6
]
3+
, radius of
Fe
3+
= 64pm
c)
[Fe(H
2
O)
6
]
2+
, radius of
Fe
2+
= 76pm
