While I could use a store bought temperature sensor, I’m doing it all old school like. After verifying that there is a correlation between temperature and conductivity via Wikipedia. I cut off a couple jumpers, realized they didn’t fit the breadboard, and then remembered I have precut jumpers that came with my arduino.
Put some tape on one and threw it in the freezer. Put a second jumper in the fridge. Going to use another for control.
That didn’t work. Cooper gave me infinite conductivity even being in the freezer for half an hour. Future efforts might use a different metal. Maybe a nickel or dime or whatever.