The burning of 20 g of SiH 4 (MW= 32.8)at constant pressure gives off 927 k) of heat. Calculate AH for this reaction.(MW SIH4(g) + 202(9) → SiO2(s) + 2H20() a. -2476 kJ/mol rxn O b.-4340 kJ/mol rxn O c. +4340 kJ/mol rxn O d.-47.2 kJ/mol rxn O e. -1520 kJ/mol rxn

1. Draw Lewis structures for ozone and for dioxygen. Using the data given below, qualitatively compare the bond enthalpies, bond orders, and bond lengths of these two compounds. O₂ (g) 20 (g) AH" = +498 kJ O(g) + O₂(g) →O, (g) AH-105 kJ

1. How many kJ of energy are released by 34.65 g of boron? Ti + 2 B -> TiB2  △ H  = 316 kJ/mol   2. How much energy in kJ is released when 14.17 g of aluminum react with an excess of copper oxide? 3 CuO + 2 Al -> 3 Cu + Al2O3  △ H  = 1190 kJ/mol   3. If 36.26 grams of aluminum is heated from 18 oC to 26 oC how much energy was required? sAl = 0.897 J/(gK)

6. Heat of Formation. Give the balanced chemical equation used to find the heat of formation of the following a) CH3COOH (1) b) Na2SO4(s)

(Q77) The standard Gibbs free energy (AG°rxn) for the formation of sulfur trioxide from sulfur dioxide and oxygen gas is -72.3 kJ/mol. The balanced chemical equation is SO2 (g) + ½ O2 (g) - - SO3 (g). What will be the Gibbs Free energy of the reaction (in kJ/mol) if it takes place at a low temperature of -25.3 °C and the concentrations of three gases are: SO2 = 0.183 M O2 = 0.146 M SO3 = 1.05 M

The reaction of CH3OH(g) with N2(g) to give HCN(g), NH3(g), and O2(g) requires 164 kJ/mol of CH3OH(g). Write a balanced chemical equation for this reaction. Include the phases of all species in the reaction.  How much heat is involved in the reaction of 65.0 g of CH3OH(g) with excess N2(g) to give HCN(g) and NH3(g) in this reaction?

1. What is the enthalpy of reaction per mole of HCl (g) in the following reaction.( Don't have to explain why) 4HCl (g) + O2 (g) → 2Cl2 (g) + 2H2O + 114.4 kJ a) -457.6 kJ / mol b) -114.4 kJ / mol c) -28.6 kJ / mol d) +114.4 kJ / mol 2. The standard enthalpy of formation of a compound represents: a) The thermal energy released by the decomposition of one mole of this compound. b) The change in enthalpy when a mole of this compound is formed from its elements under standard conditions. c) The change in enthalpy when one mole of an element turns into a compound. d)The thermal energy released by the complete combustion of one mole of this compound. e) The enthalpy change of the phase transition of one mole of this compound.

When 3.8 g A are reacted with 8.5 g D,  according to the balanced chemical equation below, 33 kJ of energy are released.  Please calculate the enthalpy for this reaction when 3 moles of G are produced.  2A + 3D = 2Z + 3G  given molar masses: A = 141.8 g/mole D = 63.996 g/ mole Z = 4.032 g/ mole G = 56.028 g/ mole

Calculate the enthalpy of decomposing hydrogen iodide to produce hydrogen and iodine.                                          2HI(g) →  I2(s) + H2(g)   I2(s) → I2(g)                                  ΔH⁰ = 124.8 kJ/mol I2(g) + H2(g) → 2HI(g)                          ΔH⁰ = - 73.0 kJ/mol