0.8 Metathesis: to exchange or not?  (Page 4/4)

Pre-lab 4: metathesis–To exchange or not

Hopefully here for the Pre-Lab

Name(Print then sign): ___________________________________________________

Lab Day: ___________________Section: ________TA__________________________

This assignment must be completed individually and turned in to your TA at the beginning of lab. You will not be allowed to begin the lab until you have completed this assignment.

1. Write molecular, complete ionic, and net ionic equations for the reactions that occur, if any, when solutions of the following substances are mixed: (a) nitric acid and barium carbonate

(b) zinc chloride and lead nitrate

(c) acetic acid and sodium hydroxide

(d) calcium nitrate and sodium carbonate

(e) ammonium chloride and potassium hydroxide

 2. Which of the following are not water soluble: $\text{Ba}({\text{NO}}_3{)}_2$ , ${\text{FeCl}}_3$ , ${\text{CuCO}}_3$ , ${\text{CuSO}}_4$ , ZnS, ${\text{ZnSO}}_4$ ?

3. Write equations for the decomposition of $H_2{\text{CO}}_3$ and $H_2{\text{SO}}_3$ .

4. At what temperature (from your graph) do ${\text{KNO}}_3$ and NaCl have the same molar solubility?

5. Which of the following are strong electrolytes: ${\text{BaCl}}_2$ , ${\text{AgNO}}_3$ , HCl, ${\text{HNO}}_3$ , ${\text{HC}}_2{H}_3{O}_2$ ?

6. Which of the following are weak electrolytes: ${\text{HNO}}_3$ , HF, HCl, ${\text{NH}}_3(\text{aq})$ , NaOH?

7. For each of the following water-soluble compounds, indicate the ions present in an aqueous solution: NaI, $K_2{\text{SO}}_4$ , NaCN, $\text{Ba}(\text{OH}{)}_2$ , $({\text{NH}}_4{)}_2{\text{SO}}_4$ .

Report 4: metathesis–To exchange or not

Hopefully here for the Report Form

Note: In preparing this report you are free to use references and consult with others. However, you may not copy from other students’work (including your laboratory partner) or misrepresent your own data (see honor code).

Name: ___________________________________________

Section: __________________________________________

Part 1: metathesis reactions

1. Copper (II) sulfate + sodium carbonate

2. Copper(II) sulfate + barium chloride

3. Copper(II) sulfate + sodium phosphate

4. Sodium carbonate + sulfuric acid

5. Sodium carbonate + hydrochloric acid

6. Cadmium chloride + sodium sulfide

7. Cadmium chloride + sodium hydroxide

8. Nickel chloride + silver nitrate

9. Nickel chloride + sodium carbonate

10. Hydrochloric acid + sodium hydroxide

11. Ammonium chloride + sodium hydroxide

12. Sodium acetate + hydrochloric acid

13. Sodium sulfide + hydrochloric acid

14. Lead nitrate + sodium sulfide

15. Lead nitrate + sulfuric acid

16. Potassium chloride + sodium nitrate

Part 2: solubility, temperature and crystallization

Table 3 Molar Solubilities of NaCl, ${\text{NaNO}}_3$ , KCl, and ${\text{KNO}}_3$ (mol/L)

• Calculate the initial molarities of ${\text{NaNO}}_3$ , KCl, NaCl, ${\text{KNO}}_3$ .

First batch of crystals

• The first batch of crystals is formed at 10°C. Describe these crystals in terms of shape, color, consistency, etc.
• Use the solubility chart to determine the identity of the crystals. Explain your answer.

Second batch of crystals

• What was the temperature of the filtrate when the second batch of crystals formed?
• Describe these crystals in terms of shape, color, consistency, etc.
• Assuming that the first batch of crystals crystallized completely, removing all of it’s ions from solution, what is the identity of the second batch of crystals? (use your solubility chart and explain your answer)

Third batch of crystals

• The reason that we see a third batch of crystals is that we don’t get complete crystallization of the salts in the 1st and 2nd batches of crystals. Assuming there is a small concentration of each ion left in solution after the second batch of crystals is formed, what is the identity of the third batch of crystals according to your solubility chart?
• Describe these crystals in terms of shape, color, consistency, etc.

BONUS QUESTION:

Describe two different tests that we could use to determine the identity of each set of crystals. To receive full credit you must give the name of the test, a description of the theory, and describe the results that you would for your proposed identity of each set of crystals. (5 points max.)