Materials List: When Should I Drink My Hot Chocolate?

Each student needs:

For Parts 1 and 2, each group needs a thermometer (the simpler and less-costly option) OR the Arduino and temperature sensor-related items listed below:

  • (optional) 1 computer with open-source Arduino Software (IDE) installed
  • (optional) 1 Arduino board, such as the assembled Arduino Uno R3 for $24.95 at Adafruit
  • (optional) 1 breadboard, such as the half-size breadboard for $5.00 at Adafruit
  • (optional) 1 DS18B20 digital temperature sensor and 4.7k Ī© resistor, such as the waterproof DS18B20 digital temperature sensor + extras for $9.95 at Adafruit
  • (optional) Thermal Sensor Program, downloaded via links in the Arduino software
  • (optional) One Wire Arduino Library, installed via Arduino software

For Part 1: Cooling Rate, each group needs:

  • 1 cup, 8-ounce paper or Styrofoam
  • boiling water, 6 fluid ounces, made with an electric kettle or on a lab hot plate
  • liquid measuring cup, for the teacher to use for all groups
  • 1 instant hot chocolate packet, such as a .71-ounce packet of NestleĀ® Hot Cocoa Mix
  • a way to measure time, up to 13 minutes, such as a stopwatch, wristwatch or wall clock

For Part 2: Specific Heat Capacity, each group needs:

  • 2 8-ounce Styrofoam coffee cups
  • 1 plastic coffee cup lid
  • scissors or utility knife, something to make small holes in the plastic lid
  • 1 stirring rod, such as coffee stirrers or lab glass stirrers
  • ~50 ml (1.69 fluid ounces) of room temperature hot chocolate liquid; save and re-use the cooled hot chocolate liquid from Part 1
  • 100 g piece of iron, such as from this hooked weight set for $38.95 at Home Science Tools
  • beaker; size may vary; in which to heat a 100 g piece of iron in boiling water
  • water, to half-fill the beaker
  • hot plate
  • tongs
  • digital scale
  • (optional) clamp or ring stand to steady the cup
  • Arduino and temperature sensor (same as above) OR thermometer
  • lab safety gear (same as above)