Question

The chemical box contains an “unknown” chemical that is a sulfate, carbonate, or phosphate salt. Using the procedures learned earlier in this experiment, determine which type of salt is contained in the unknown solution. Remember that the results need to match those from the previous experiments for a positive identification result. Other reactions may happen, but these results do not give a definitive answer with respect to what compound is in the solution.

Use a permanent market to label three test tubes “Carbonate Ion Test,” “Sulfate Ion Test,” and “Phosphate Ion Test.”

Remove the twist cap and dropper lid from the unknown solution.

Use the 10 mL graduated cylinder to measure and pour 2 mL of the unknown solution into each test tube.

Perform the Carbonate Ion Test by pipetting five drops of acetic acid into the test tube labeled “Carbonate Ion Test.” Use your camera (or smart phone) to take a picture of the results. Be sure to properly identify the picture and send it to your instructor along with the lab questions.

Perform the Sulfate Ion Test by pipetting one drop of acetic acid (using the pipette from Step 5) and four drops of barium chloride (using a clean pipette) into the test tube labeled “Sulfate Ion Test.” Use your camera (or smart phone) to take a picture of the results. Be sure to properly identify the picture and send it to your instructor along with the answers to the lab questions.

Perform the Phosphate Ion Test by pipetting 2 mL of 0.1 M sodium phosphate tribasic into the test tube labeled “Phosphate Ion Test.” Use your camera (or smart phone) to take a picture of the results. Be sure to properly identify the picture and send it to your instructor along with the answers to the lab questions.

Record the results of each test in Table 4. Record a positive result if a reaction took place and a negative result if there was no reaction.

Table 4: Determination of an Unknown Results

My observations were the Phosphate had the only change in color of all the mixtures

Answer 1