Part of a silica process is outlined in the following steps:1. Heat 15 mol% soda-85 mol% s...

Part of a silica process is outlined in the following steps:

1. Heat 15 mol% soda-85 mol% silica to 1800°C.

2. Cool to 1200°C.

3. At constant temperature, increase soda content to 25 mol%.

4. Cool to 1000°C.

5. At constant temperature, increase soda content to 35 mol%. What, if any, solids are formed during this process? See Figure.