Final answer:
To calculate the needed mass of an endothermic salt for a temperature change, you can use the heat equation q=mcΔT and average the data from two experiments.
Step-by-step explanation:
The student is tasked with calculating the amount (mass in grams) of an endothermic salt needed to effect a specific temperature change in a chemical reaction. To solve this, we use the formula q = mcΔT, where q is the heat absorbed or released, m is the mass of the substance, c is the specific heat, and ΔT is the change in temperature. By averaging the data from two trials with different masses of salt, we can determine the average heat change per gram of salt and then use this information to find the mass of salt needed to achieve the desired temperature change in the system.