List of top Geology Questions on Phase equilibria asked in IIT JAM GG

The following diagram represents a binary phase diagram for the system A–B at atmospheric pressure. If ‘X’ is the initial composition of melt, then the amount of melt that converts to solid when the magma cools from 1400 °C to 1250 °C is ________ %. (Round off to two decimal places.) 

A melt containing 900 moles of anorthite and 100 moles of diopside undergoes crystallization. The number of moles of anorthite that crystallize as the melt composition moves from P to Q is ..........