What is the minimum operating temperature of a silicon arc furnace?	1,700°C.
Name the four components of the furnace charge.	Clean quartzite, metallurgical-grade coke, charcoal, and wood chips.
Why are wood chips added to the furnace charge?	To keep the charge porous so reaction gases can escape.
Write the carbothermic reduction equation.	SiO₂ + 2C → Si + 2CO.
What gas burns continuously at the top of a running arc furnace?	Carbon monoxide (CO).
How much electricity does producing one ton of MG-Si consume?	Roughly 13–14 megawatt-hours.
Why do silicon smelters cluster near hydroelectric dams?	Because the process is so energy-intensive — 13–14 MWh per ton — that cheap electricity is a major cost driver.
What is metallurgical-grade silicon’s purity after smelting?	98–99%.
What fraction of all silicon produced ends its career as MG-Si (never reaching semiconductor use)?	About 80%.
What are the three main non-semiconductor uses of MG-Si named in the chapter?	Aluminum alloying, silicone polymers, and ferrosilicon for steel-making.