What thickness (in cm) is the silicon block (density = 2.33 g/cm3) that is 2.87 cm wide and long necessary to react with 91.3 g of Cr₂O₃ by the reaction: 3 Si (s) + 2 Cr₂O₃ (s) → 3 SiO₂ (s) + 4 Cr (l)?

Question

Quizplus · Accepted Answer

To find the thickness, first calculate the moles of Cr₂O₃ using its molar mass (151.99 g/mol), then use the stoichiometry of the reaction to find moles of Si needed. Convert moles of Si to grams using its molar mass (28.09 g/mol), and then use the density of silicon to find the volume. Finally, divide the volume by the area (2.87 cm x 2.87 cm) to find the thickness.

What Thickness (In Cm) Is the Silicon Block (Density =