Final answer:
When the temperature reaches 600°C, any remaining liquid quenches to form glass. The specific rock formed is silica glass. The temperature of the substance in its standard state is 1600°C.
Step-by-step explanation:
When the temperature reaches 600 °C, any remaining liquid quenches to form glass. In this case, the rock that has formed is glass, specifically silica glass. Silica glass is formed when quartz melts and cools without crystallizing. It has a random arrangement of SiO4 tetrahedra, giving it the characteristics of a supercooled liquid.
The temperature of the substance when it is in its standard state, or the melting point of quartz, is 1600 °C. At this temperature, quartz melts and yields a viscous liquid. When the liquid cools, it typically forms silica glass.