Observation and Experiment

Observation and Experiment
Data Table A. The Overall Reaction
What are the physical properties of the individual substances?
Chemical Observation

Calcium Chloride Grainy, White

Sodium Bicarbonate White, flour texture

Phenol Red Solution The color of Hawaiian punch, thin consistency, semi- transparent
What happens when the substances are mixed together?

Observations Calcium Chloride- Foams and heats up when mixed with the phenol red. Turned orange
Sodium Bicarbonate- Turned orange, dissolved
What individual interactions are responsible for the observed changes?

Questions How come the sodium bicarbonate dissolved?
Why did the calcium chloride heat up?
What changed the two chemicals’ colors?

Data Table B. Control Experiments
Number Calcium
Chloride Sodium
Bicarbonate Phenol
Red Water Observations

1    Calcium chloride heated up and foamed, turned orange
Sodium bicarbonate dissolved, turned orange

2    Calcium chloride heated, no color change
Sodium bicarbonate foamed, no color change

3   Calcium chloride heated, didn’t diffuse with phenol red, turned orange

4   Sodium bicarbonate didn’t dissolve, turned pink, no temperature change

Discussion Questions:
1. It appears that when calcium chloride is mixed with a liquid such as phenol red, and water, the liquid triggers the temperature change. The calcium chloride foams and heats up, which causes the temperature to rise.
2. No, because when the calcium chloride was mixed with the sodium bicarbonate, the temperature still rose. However the temperature changed during the controlled experiment of just calcium chloride and water was mixed together. When my lab partner and I put sodium bicarbonate and water into the same bag, there was no temperature change.
3. The color changed from red to yellow was observed in the overall reaction of the substances. The control experiments do provide evidence concerning the interaction responsible for the observed