Last week we worked on a lab which included physical and chemical change. We worked on four different labs. We worked on two candles; one small and one big, a marshmallow, and a sugar cubes. All these labs had some chemical changes and some physical changes.
This is an example of chemical change.
This is an example of physical change.
The small candle was the first lab we did. In this lab, we watched the candle burn down and melt. You were clearly able to see the wax dripping down the candle. When the candle was not put on fire, it was a physical change. When we set it on fire, it became chemical change. Next, we lit a bigger candle. For this candle, we mixed several substances together and poured it over the big candle and it instantly blew out. This was one of my favorites because I have never seen anything like it before. Again, just like the little candle when this candle was not lit it was a physical change. When it got lit, it became chemical change.
This picture shows a big and small lit candle.
The next lab was burning the marshmallow. In this lab, we had to taste the marshmallow before it was burnt and after it was burnt. Before it was burnt, it was physical change. After it was burnt, it was chemical change. Before I burnt it, the marshmallow had a sweet taste and soft feeling. After I burnt it over the bunsen burner, it tasted burned and it became crispy. The original white color of the marshmallow was gone. It was dark brown, almost black. This happened because I left mine on the fire for a longer time. This was my favorite lab because we got to eat it. It reminded me of s'mores. I really enjoyed this lab.
This is how my marshmallow looked after I roasted it over the bunsen burner.
Finally, comes the sugar cube lab. We crushed two of the four sugar cubes and poured it into the test tube. Then our group put the test tubes with the sugar over the bunsen burner. It was boiling and caramelizing the sugar. Then, all of a sudden the sugar came up like it was going to explode. We turned off the bunsen burner and took the tongs and put the test tubes down. The sugar was totally burnt just like the marshmallow. The sugar would not come out of the test tube. The test tube was broken apart and we tasted the burnt sugar. It tasted really bad. Although, this was not my favorite lab it taught me a lot. This can help me in the future when I cook.
This picture shows burnt sugar.
All in all, these labs all had a purpose to them. It was to show us the states of matter. It showed us physical and chemical changes. All the labs had to do with fire. The marshmallow and sugar lab were similar in my opinion. They both started out as white. Then they turned burnt which made them brown/black. I enjoyed all these labs and I hope we get to do something like this again.