Sand Is Converted to Pure Silicon in a Three-Step Process

question 94

Multiple Choice

Sand is converted to pure silicon in a three-step process. The final step in this process is as follows. SiCl₄(g) + 2Mg(s) → 2MgCl(s) + Si(s) ΔH°_rxn = -625.6 kJ/mol
What is the enthalpy change if 25.0 mol of silicon tetrachloride is converted to elemental silicon?

• A) -25.0 kJ
• B) -626 kJ
• C) -1.56 × l0⁴ kJ
• D) -3.13 × 10⁴ kJ
• E) -3.13 × 10³ kJ

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