C

For our third class we decided to explore chemical engineering through making ice cream. We began the lesson by talking about very basic chemistry and what chemical engineers do. We explained the chemistry behind salt lowering the freezing point of water and how this reaction could be used to make ice cream. 

Before the class we prepared the ice cream mixture in quart-sized ziplock bags. We placed these bags into an extra ziplock bag just to be safe so that the ice cream and salt/water mixture did not come in contact. The students placed the bags of ice cream mixture into gallon sized bags. The students then lined up to receive about 2 cups of ice and 1/2 cup of salt. The students shook the bag for about 10 minutes. For some of the students their bags started leaking so we had to double up the gallon sized bags as well.

Each pair made their own bag. When they finished shaking the bags the students lined up at the sink and Andrea and I emptied their salt/water mixtures into the sink and divided the ice cream. This worked really well to avoid mess and fighting over who got more.

This lesson went really well and fit nicely into one hour.