S Essay, Research Paper

Qualitative Analysis of Group IV Ions

The composition of my unknown #J10 is Barium, Calcium, and Sodium.

Confirmation of Ba2+: After I added .5 mL of 6M acetic acid to the precipitate from step

# 2 the solid dissolved. A yellow precipitate formed after adding 1 mL of water, 2 drops of 6M NH3, and .5 mL 0f 1M K2CrO4. This confirmed the presence of barium.

Confirmation of Ca2+: I added 6M sodium hydroxide to the orange solution from step

three until it was basic (solution turned yellow). A white precipitate formed after adding K2C2O4 confirming the presence of calcium. I also preformed a flame test to confirm the presence of calcium. After dissolving the solid with HCl I observed a red flame due to calcium.

Confirmation of Na+: I confirmed the presence of sodium through the process of

elimination and a guess on why the flame test did not completely confirm its presence. When performing the flame test I observed a green flame instead of a yellow flame. A yellow flame would confirm the presence of sodium. When I looked closer at the flame I did observe small traces of yellow. I feel that the green flame of barium prevented me from seeing sodium?s less distinct yellow flame.