Consider the reaction: H2(g) + (1/2)O2(g) -------> H2O(l) ΔH° = -286 kJ Which of the following is true?
(Select all that apply)
the reaction is endothermic
heat is given off by the surroundings
the reaction is exothermic
heat is absorbed by the system
the enthalpy of the products is less than the that of the reactants

Consider the reaction: H2(g) + (1/2)O2(g) -------> H2O(l) ΔH° = -286 kJ Which of the following...
2 pts Question 14 Consider the reaction 2H2(g) + O2(g) → 2H2O(l) AH = -286 kJ Which of the following is true? The reaction is exothermic The reaction is endothermic The reaction is neutral with respect to energy change Heat is absorbed by the system Information is not enough to tell about the energy change
Consider the following data. 2 H2(g) + O2(g) 2 H2O(l) ΔH = -571.7 kJ N2O5(g) + H2O(l) 2 HNO3(l) ΔH = -92.0 kJ N2(g) + 3 O2(g) + H2(g) 2 HNO3O(l) ΔH = -348.2 kJ Use Hess's law to calculate ΔH for the reaction below. 2 N2O5(g) 2 N2(g) + 5 O2(g) ΔH = _____kJ
6. Given H2(g) + 22 O2(g) → H2O(1), AH° = -286 kJ/mol, Determine the standard enthalpy change for the reaction 2H2O(l) → 2H2(g) + O2(g) (2 pt)
Determine ΔH for the following reaction: N2(g) + 2 H2(g) → N2H4(l) Given: N2H4(l) + O2(g) → N2(g) + 2 H2O(l) ΔH = -622.2 kJ H2(g) + 1/2 O2(g) → H2O(l) ΔH = -285.8 kJ
Consider the following chemical reaction. NH3(g) + 2 O2(g) → HNO3(aq) + H2O(l) Calculate the change in enthalpy (ΔH) for this reaction, using Hess' law and the enthalpy changes for the reactions given below. (1a) 4 NH3(g) + 5 O2(g) → 4 NO(g) + 6 H2O(l); ΔH = −1166.0 kJ/mol (2a) 2 NO(g) + O2(g) → 2 NO2(g); ΔH = −116.2 kJ/mol (3a) 3 NO2(g) + H2O(l) → 2 HNO3(aq) + NO(g); ΔH = −137.3 kJ/mol
If H2 + 1/2 O2 ----> H2O has an enthalpy of -286 KJ, the enthalpy change for making 573 grams of H2 is ______ (a number)
13 For the reaction H2(g) + LaTeX: \frac{1}{2}1 2O2(g) --> H2O(l) LaTeX: \DeltaΔH = -286 kJ/mol Calculate the enthalpy change when 2.8 g of water is produced. 44.45 kJ 102.14 kJ 800.8 kJ –800.8 kJ –44.45 kJ
18. For the reaction H2(g) + LaTeX: \frac{1}{2}1 2O2(g) --> H2O(l) LaTeX: \DeltaΔH = -286 kJ/mol Calculate the enthalpy change when 4.73 g of hydrogen gas is reacted with excess oxygen.
For the following reaction 3 O2 (g) → 2 O3 (g) ΔH = +286 kJ What is the ΔH when 16.0 g of O3 are produced
When 4 moles of HCKg) react with O2(g) to form H2O(g) and Cl2(g) according to the following equation, 114 kJ of energy are evolved. 4HCK(g) + O2(g) 2H2O(g) + 2C12(e) Reactants Products Enthalpy Enthalpy Products Reactants (A) (B) Which of the enthalpy diagrams above represents this reaction? Is this reaction endothermic or exothermic?