Need help to solve these questions with explanation. Pllease solve all questions please 12. What is...

1) SiCl₄ + 2H₂O -------> SiO₂ + 4HCl

H_f(SiCl4) = -640.1kJ/mol H_f(H2O) = -258.8 kJ/mol H_f(SiO2) = -910.9kJ/mol   H_f(HCl) = -92.3kJ/mol

H_rxn = n H_f(products) - n H_f(reactants)

n H_f(products) = -910.9+ 4(-92.3) = -1280.1 kJ/mol

n H_f(reactants) = -640.1+ 2(-285.8) = -1211.7 kJ/mol

H_rxn = -1280.1 - (-1211.7) = -68.4 kJ/mol

2) 2C₂H₂ + 5O₂ -----------> 4CO₂ + 2H₂O   H = -2601 kJ ------- MULTIPLY BY 2

C₈H₈ + 10O₂ -----------> 8CO₂ + 4H₂O   H = - 4393 kJ ------ REVERSE THE REACTION

2( 2C₂H₂ + 5O₂ -----------> 4CO₂ + 2H₂O)   H = 2(-2601) kJ

4C₂H₂ + 10O₂ -----------> 8CO₂ + 4H₂O    H = -5202 kJ ---- 1

8CO₂ + 4H₂O -----------> C₈H₈ + 10O₂H = +4393 kJ ----- 2

Adding equation 1 and 2 gives the equation 3

   4C₂H_2(g) ------> C₈H_8(l) --------------- 3  H = ? kJ

H = H_eq1 + H_eq2 = -5202+4393 = -809 kJ

3) 2HBr -----> H₂ + Br₂

H_f(H-H) = 436 kJ/mol H_f(Br-Br) = 193 kJ/mol H_f(H-Br) = 366 kJ/mol

H_rxn = n H_f(products) - n H_f(reactants)

n H_f(products) = 436 + 193  = 629 kJ/mol

n H_f(reactants) = 2(366) = 732 kJ/mol

H_rxn = 732 - 629 = +103 kJ/mol