In designing a bomb calorimeter, which material property is most crucial for ensuring precise temperature measurements during calibration and subsequent combustion tests?

The most crucial property is the material’s thermal conductivity, because a high conductivity lets heat spread quickly and evenly throughout the calorimeter. When the bomb is heated or when a reaction occurs, a high‑conductivity material keeps the temperature uniform so that the thermometer reads the true bulk temperature. If the conductivity were low, temperature gradients would form, making the thermometer’s reading unreliable and the measured heat of combustion inaccurate. For example, using a copper vessel instead of a plastic one allows the heat from the combustion to reach the thermometer almost instantaneously, giving a precise temperature measurement.