pg. 10 Selected Chemistry Assignment Answers Unit 5: Chemical Equations and Reactions & Stoichiometry Chapter 8: Chemical Equations and Reactions 8.1: Describing Chemical Reactions (Section Review on pg. 266) 5. C3H8 + O2 ? CO2 + H2O 6. C3H8 (g) + O2 (g) ? CO2 (g) + H2O (l) 9. silicon tetrachloride + magnesium ? silicon + magnesium chloride ; SiCl4 (g) + Mg (s) ? Si (s) + MgCl2 (s) 10. magnesium + oxygen ? magnesium oxide ; Mg (s) + O2 (g) ? MgO (s) 8.2: Balancing Chemical Equations (Practice on pg. 269) 1. P4 + 5 O2 ? 2 P2O5 2. C3H8 + 5 O2 ? 3 CO2 + 4 H2O 3. Ca2Si + 4 Cl2 ? 2 CaCl2 + SiCl4 4. 2 Si + CO2 ? SiC + SiO2 (Practice on pg. 271)