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How does silicon in ferrosilicon act as a reducing agent?

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A color-coded periodic table of the elements displays each element's symbol and atomic number, with categories such as alkali metals, noble gases, halogens, transition metals, and actinoid elements distinguished by different background colors. — carbon group element Modern version of the periodic table of the elements (printable).

In metallurgy, silicon acts as a strong reducing agent by donating electrons to other substances, a process that effectively removes oxygen from metal oxides to liberate the pure metal.1

When used in the form of ferrosilicon—an alloy of iron and silicon—the silicon component facilitates this reduction. A notable application of this chemical property is the use of ferrosilicon to liberate magnesium from its oxide. Additionally, silicon is widely employed in the steel industry as a deoxidizer, where it reacts with oxygen to help purify the molten metal.123

While carbon is also a well-known high-temperature reducing agent used to extract various metals from their ores, silicon is specifically valued in these alloys for its ability to perform similar chemical reductions in metallurgical processing.1