Instructions:

Based on the above phase diagram answer the following questions:

a$)$ At what temperature the eutectic reaction takes place?

b$)$ What phases are obtained at the eutectic reaction?

c$)$ What is maximum composition of alumina in the Mullite phase located in the two phase region composed of Mullite$($ss$)$

Cristobalite $($blue region$)?$d$)$ Deduct what is the composition of Cristobalite?

f$)$ If the weight fraction of mullite in the blue region is $0\mathrm{.}822$ and the initial concentration of alumina is Co$=0\mathrm{.}6$ what is the concentraion of silica?