How does VSEPR help determine the shape of the molecule? A) The shape of the molecule is determined by the mass of the nuclei of different atoms in molecule, so that the mass is as evenly distributed as possible.
B) The shape of the molecule is determined by the valence electrons of the different atoms within a molecule repelling each other, so the atoms are as far apart as possible from any other valence shell.
C) The shape of the molecule is determined by the electronegativity values of the different atoms within a molecule, so the atoms are spaced apart based on decreasing electronegativity.

B) The shape of the molecule is determined by the valence electrons of the different atoms within a molecule repelling each other, so the atoms are as far apart as possible from any other valence shell.

Explanation:

VSEPR denotes Valence Electron Pair Repulsion.

It is one of the theories used to predict the model of a compound or molecule.

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%