Final answer:
Prograde metamorphic reactions do not typically liberate aluminum, as it is bound within silicate minerals, whereas water, carbon dioxide, and silica are common byproducts of metamorphism.
Step-by-step explanation:
The student has asked about prograde metamorphic reactions that do not liberate certain compounds. Specifically, prograde metamorphic reactions do not typically release aluminum because it is a major component in many silicate minerals. In contrast, water (H2O), carbon dioxide (CO2), and silica (SiO2) are often liberated during metamorphic reactions as they are part of the dehydration or decarbonation processes when minerals such as chlorite, biotite, garnet, staurolite, kyanite, and andalusite form from a shale protolith. These reactions typically occur under specific pressure-temperature conditions which can indicate the geological history of the rock, such as whether the area has undergone continent-continent collision (medium-pressure terranes) or if there is an elevated geothermal gradient due to divergent zones or unusual ocean-continent collision zones (low-pressure terranes).