Question

1. Group IV ions

2. During your Qualitative Analysis, the ions in this group will not precipitate as chlorides, sulfides or hydroxides

3. The test for ammonium ions must be done first because

4. To detect K+ (aq) in a solution that is known to contain only K+ (aq) and Na+ (aq)

5. To detect Ca2+ (aq) in a solution that is known to contain only Ca2+ (aq), Fe3+ (aq) and Al3+ (aq), you must

6. To detect Mg2+ (aq) in a solution that is known to contain only Mg2+ (aq), Cu2+ (aq) and Na+ (aq)

7. These ions form few insoluble compounds

8. According to your flow chart, how will you reduce Mg3+ (aq) to Mg 2+ (aq)?

9. During the analysis of your Qual IV unknown, how will you precipitate CaC2 O4 (s) from a solution containing Mg2+ (aq) and Ca2+ (aq) ions ?

10. According to your flow chart, how will you oxidize K+ (aq)?

Match with one of the following:

A. This ion is not reduced

B. first precipitate out Group III ions

C. first precipitate out Group II ions

D. use cobalt glass to obscure the yellow flame, look for a violet color

E. K+ (aq) and Na+ (aq)

F. add 5M NH3 (aq), 2M NH4 Cl and 0.2M (NH4 )2 C2 O4

G. have no common theme

H. This ion is not oxidized

I. Group IV

J. reagents containing this ion are added in later steps

Answer 1

1.. Group IV ions

2. During your Qualitative Analysis, the ions in this group will not precipitate as chlorides, sulfides or hydroxides

I. Group IV

3. The test for ammonium ions must be done first because

J. reagents containing this ion are added in later steps

4. To detect K+ (aq) in a solution that is known to contain only K+ (aq) and Na+ (aq)

D. use cobalt glass to obscure the yellow flame, look for a violet color

5. To detect Ca2+ (aq) in a solution that is known to contain only Ca2+ (aq), Fe3+ (aq) and Al3+ (aq), you must

F. add 5M NH3 (aq), 2M NH4 Cl and 0.2M (NH4 )2 C2 O4

6. To detect Mg2+ (aq) in a solution that is known to contain only Mg2+ (aq), Cu2+ (aq) and Na+ (aq)

C. first precipitate out Group II ions

7. These ions form few insoluble compounds

E. K+ (aq) and Na+ (aq)

8. According to your flow chart, how will you reduce Mg3+ (aq) to Mg 2+ (aq)?

A. This ion is not reduced

9. During the analysis of your Qual IV unknown, how will you precipitate CaC2 O4 (s) from a solution containing Mg2+ (aq) and Ca2+ (aq) ions ?

B. first precipitate out Group III ions

10. According to your flow chart, how will you oxidize K+ (aq)?

H. This ion is not oxidized