Title: Physical/Chemical Changes
Purpose: To determine the distinct characteristics of physical and chemical changes and to be able to distinguish between the two.
Procedure: I placed 4 drops of each chemical listed in wells A1-B2. Wells A2 and B1 have two observations as they had two chemical reactions. When a chemical mixture did in fact produce a chemical reaction, I listed it in the “Chemical change (Y/N)” column and all other observations can be found in the “Observations” column.
|Well |Chemical #1 |Chemical #2 |Observations |Chemical change (Y/N) |
|A1 |NaHCO3 ...view middle of the document...
|A4 |NaOH |C20H14O4 |Chemicals turned magenta and became shiny. |Yes |
| |Sodium Hydroxide |Phenolphthalein | | |
|A5 |HCl |C20H14O4 |No changes. |No |
| |Hydrochloric |Phenolphthalein | | |
| |Acid | | | |
|A6 |NaOH |AgNO3 |Gray clumps began to separate from the clear |Yes |
| |Sodium Hydroxide |Silver Nitrate |liquid. | |
|B1 |AgNO3 |NH4 |Observation 1: Chemicals turned white together. |1: Yes |
| |Silver Nitrate |OH |Observation 2: Stain on paper towel turned dark |2: Yes |
| | |Aqueous Ammonia |purple. | |
|B2 |NH4 |CuSO4 |Blue clumps separated from clear liquid and the |Yes |
| |OH |Copper Sulfate |blue dye became brighter and lighter. Mixture is| |
| |Aqueous Ammonia | |iridescent in the light. | |
|Chemical |Initial Observation |Heating Observation |Burning Observation |
|Mg |Small, silver beads of metal. Solid |Magnesium bead expanded and turned a |Tweezers changed the shape of the shape of|
| |state of matter and not malleable. |darker shade of gray. After a longer |the magnesium bead as the fire made it |
| | |duration over the flame, the bead |softer and more malleable. |
| | |turned the surrounding test tube glass | |
| | |black and created a white fog in the | |
| | |tube. ...