How does this error affect the final temperature measured in the experiment (compared to the value that would be obtained without the error)? While using a coffee cup calorimeter in this experiment, some heat was lost to the environment. How would this affect the magnitude of q and ΔH? Magnesium, using a coffee cup calorimeter and measuring the final temp when MgO is added to HCL, and repeated using a strip of Mg instead of the powder MgO.