If a rock containing kyanite and sillimanite were to undergo an increase in pressure, what must happen to temperature in order for that rock to continue to have stable kyanite and sillimanite?
A) temperature must increase
B) temperature must decrease
C) temperature must stay the same
D) It is impossible for it to continue to have stable kyanite and sillimanite.

Question

Quizplus · Accepted Answer

Kyanite and sillimanite are polymorphs of Al2SiO5, meaning they have the same chemical composition but different crystal structures due to their formation under different conditions of temperature and pressure. Kyanite is stable at high pressure and lower temperature, while sillimanite is stable at high temperature. If pressure increases, temperature must also increase to maintain a condition where both kyanite and sillimanite can coexist stably.

If a Rock Containing Kyanite and Sillimanite Were to Undergo