7. What is the enthalpy is 36 g of HCl react? CHCI (1) + 3 HCI (9) → CH. (g) + 3 Clz (9) AH = 336 kJ/mol rxr
a. 4032 kJ
b. 336 kJ
C. 212 ki
d.. 112kj

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%