Blog Post Week 15

 Week 15

Today in lab we focused on the last experiment we tried to get introduced to chemistry: baking soda and vinegar. With this, we kept in mind our observations from last time: the cold temperature, the bubbling reaction, and evaporation. This time we wanted to be able to prove that a chemical reaction or phase change does not change the amount of matter. Therefore we took measurements and tried different ways to make sure all of the gas was captured. 

Baking soda and vinegar

Why did the bag expand? Why did it get cold? Why did it fizzle? Why did it stop?

How do we prove to kids that when a log burns, its matter is conserved? etc.

To begin this experiment we did it the same as we did during our first time; we added a bunch of baking soda to the bag, then just added a bunch of vinegar and closed the bag to observe the chemical reaction.  We realized this experiment would not prove to students that matter is conserved because we couldn't close the bag fast enough.

All of our measurements: 7.3 grams plastic bag

49.3 grams beaker

3.2 grams baking soda

6.1 grams of vinegar 

should be: 9.3 grams of baking soda and vinegar

should be: 16.6 baking soda, vinegar and bag

16.2 grams bag w baking soda and vinegar 

8.9 grams baking soda and vinegar after mixed 

lost .4 grams of mass due to human error of not closing the bag fast enough

this is because of the chemical reaction beginning the second you add vinegar to the baking soda so it evaporates   

We then talked about pushing up the middle of the bag and putting the baking soda on one side and vinegar on the other and sealing the bag up before mixing it. This would reduce the chances of human error interfering with the amount of matter proven to be conserved.