半导体工业用石英砂做原料,通过三个重要反应生产单质硅:
①SiO2(s)+2C(s) =" Si(s)+2CO(g) " △H =" +682.44" kJ/mol
(石英砂) (粗硅)
②Si(s)+2Cl2(g) = SiCl4(g) △H = -657.01kJ/mol
(粗硅)
③SiCl4(g)+2Mg(s) = 2MgCl2(s)+Si(s) △H =" -625.63" kJ/mol
(纯硅)
生产1.00kg纯硅的总反应热为
A.+2.43×104kJ | B.-2.35×104kJ | C.-2.23×104kJ | D.-2.14×104kJ |