Consider the chemical equations shown here.
2H, (9)+0,(g) → 2H, O(9) AH, = -483.6 kJ + 2 = -241.8 kJ/mol
30,(9) ► 20,(g) AH, = 284.6 kJ = 2 = 142.3 kJ/mol
What is the overall enthalpy of reaction for the equation shown below?
3H2(9)+02 (9). 310 ()

1. for the first question, we must find the mass of the anhydrous salt, mgso₄. the molar mass for mgso₄·7h₂o is 246.47 g/mol, while that of mgso₄ is 120.37 g/mol.7.834 g mgso₄·7h₂o * 1 mol mgso₄·7h₂o/246.47 g * 1 mol mgso₄/1 mol mgso₄·7h₂o * 20.37 g mgso₄/mol = 0.647 g mgso₄

2. mass of water = mass of sample - mass of anhydrous salemass of water = 7.834 - 0.647 = 7.19 gpercent water in hydrate = 7.19/7.834 * 100 = 91.74%

i think the answer is terrae but not 100 percent sure. ▓▬▬ §