Name:__________________
Date:___________
ACT Chromatography
Paper chromatography can be used to identify metal
ions in wastewater. A drop of sample solution is placed
on filter paper. The bottom of the paper is set in a solvent
that travels up the paper (see Figure 1).
Period:________
1.
The information in Tables 1 and 2 supports
the conclusion that Sample 3 contains:
A.Cu2+ and Cd2+ only.
B.Co2+ and Hg2+ only.
C.Ni2+, Co2+, and Cd2+ only.
D.Ni2+, Cd2+, and Hg2+ only
2.
Based on the information in Tables 1 and 2,
one can conclude that Sample 2 contains:
F.1 metal ion only.
G.2 metal ions only.
H.either 1 or 2 metal ions.
J.more than 2 metal ions.
Figure 1
The solvent carries the ions up the paper. Some ions move
faster, and therefore farther than others, resulting in a
separation as they move up the paper. The paper is dried,
then stained, causing the ions to appear as colored spots.
Rf values are calculated for each spot:
Table 1 shows Rf values for 5 ions. Table 2 shows Rf
values from 3 samples of wastewater. The same solvent
was used for all ions and samples.
3.
Based on the information in Table 1, which
of the following lists the metal ions in order
from the fastest to slowest speed with
which they moved up the paper?
A.Hg2+, Cd2+, Cu2+, Co2+, Ni2+
B.Cd2+, Cu2+, Co2+, Hg2+, Ni2+
C.Ni2+, Hg2+, Co2+, Cu2+, Cd2+
D.Ni2+, Co2+, Cu2+, Cd2+, Hg2+
Name:__________________
Date:___________
Table 1
Distance
Molar mass traveled
(g/mole)
(cm)
Ion
Rf
Spot color
Nickel
(Ni2+)
58.7
0.8
0.08 pink
Cobalt
(Co2+)
58.9
3.5
0.35 brown-black
Copper
(Cu2+)
63.5
6.0
0.60 blue
Cadmium
(Cd2+)
112.4
7.8
0.78 yellow
Mercury
(Hg2+)
200.6
9.5
0.95 brown-black
Period:________
4.
Based on the information in Table 2, which
of the following figures best illustrates the
appearance of the filter paper after Sample
1 was analyzed?
F.
G.
Table 1 adapted from Thomas McCullough, CSC, and
Marissa Curlee, "Qualitative Analysis of Cations Using Paper
Chromatography." ©1993 by the American Chemical Society.
H.
J.
Table 2
Sample
Rf
Spot color
1
0.60
0.78
blue
yellow
2
0.35
0.95
brown-black
brown-black
3
0.08
0.78
0.95
pink
yellow
brown-black
Note: Samples contain only the metal
ions listed in Table 1.
5.
Based on the information in Table 1, to best
identify a metal ion using paper
chromatography, one should know the:
A.spot color for the ion only.
B.distance the solvent traveled only.
C.Rf value and spot color for the ion only.
D.distance the solvent traveled and spot
color of the ion only.