Our differential scanning thermal analyzer uses phase changes to identify unknown materials. It applies heat to two chambers: one with a substance and the other empty, and measures the temperature in the chambers. By comparing the graphs and identifying spikes in temperature, you can tell what the sample is made up of. For example, a sample of water might show a temperature spike at 100˚C, or paraffin wax might change states at 25˚C. A mixture would show spikes at both locations. The tool can be constructed from materials accessible in Rwanda, and the cost in the US was well under $50. Other thermal analyzers of this type start at $20,000, so ours is 1/400 the cost of its next­-lowest competitor. It requires only simple tools: a toaster/Nichrome wire, clay, electricity, and tape that can withstand high heat. We are hopeful that, in Rwanda, our device will assist in improving chemistry labs.