Name: ______Period: ______

SOLUBILITY AND IDENTIFICATION OF UNKNOWNS

Objective: To identify Unknown U__ and Unknown #5__

Apparatus/Chemicals:

1)Spot Plate

2)Solution 1

3)Solution 2

4)Solution 3

5)Solution 4

6)Solution A

7)Solution B

8)Solution C

9)Unknown U__

10)Unknown #5__

Procedure:

  1. In a spot plate combine 2 drops of each of the solutions in the following manner, recording your observations, including the color of the solutions/precipitates.

A / B / C
1
2
3
4
U__
#5__
Check
Check

(You will need to clean the spot plate after testing Solutions 1,2,3, and 4 with Solutions A, B, and C.)

  1. Identify the Unknows:
  2. Unknow U__ is Solution ___ (1, 2, 3, or 4)
  3. Unknown #5__ is a combination of ____ and ____ (1&2, 1&3, 1&4, 2&3, 2&4, or 3&4)

A / B / C
1
2
3
4

Reactions: (Put a box around the formulas of any precipitates)

1A / + / ↔ / ↔
1B / + / ↔ / ↔
1C / + / ↔ / ↔
2A / + / ↔ / ↔
2B / + / ↔ / ↔
2C / + / ↔ / ↔
3A / + / ↔ / ↔
3B / + / ↔ / ↔
3C / + / ↔ / ↔
4A / + / ↔ / ↔
4B / + / ↔ / ↔
4C / + / ↔ / ↔

Names of group members

______

______

______

______

Preparation of Solutions

Group # / Solute / Grams of solute / % m/m
1 / NaCl
2 / Na2SO4
3 / K2CrO4
4 / K4Fe(CN)6∙3H2O
5 / AgNO3
6 / Ba(NO3)2
7 / Zn(NO3)2∙6H2O

You are doing the calculations necessary to make 500 mL of a 0.1 M solution.

Assuming that the solute does not contribute to the volume of the solution, complete your group’s portion of the table, showing work below.