Effects of Surface and Interfacial Energy on Microstructure $[6$ pts$]$

a$.$ The surface energy increases with concentration of CaO in the system CaO$-$

$Si{O}_2.$ Predict the spatial distribution with respect to composition for $Si{O}_2$ with

CaO dissolved in it$.$ Explain. $[3$ pts$]$

b$.$ The surface energy decreases with concentration of $K_{2}O$ in the system $K_{2}O-$

$Si{O}_2.$ Predict the spatial distribution with respect to composition for $Si{O}_2$ with

$K_{2}O$ dissolved in it$.$ Explain. $[3$ pts$]$