The general objective of this thesis was to design and build a device to evaluate the specific heat of liquids and the thermal conductivity of solid materials. The device is composed of the following components: a stainless steel parallelepiped box, an electric heater as the heat source, and the following digital instruments: a temperature controller with a thermocouple sensor, an infrared digital thermometer, a metal probe thermometer, and a voltage and amperage meter. The liquids used had a mass of 0.2 kg and included: aguaje juice (with 12 % dissolved solids) and sugar solutions at: 10 %, 25 % and 40 % by weight. The specific heat values obtained were: 3889.80 J/(kg.°C), 3928.24 J/(kg. °C), 3592.21 J/(kg.°C) y 3530.92 J/(kg.°C), respectively. This indicated that the higher the concentration of dissolved solids, the lower the corresponding specific heat, demonstrating an inverse re...