5. For the reaction: 2 H. (g) + O (g) → 2 HOD. how many grams of water can be made from 175L of oxygen gas and an excess of hydrogen at a pressure of 1254 torr and a temperature of 20.0 C2​

c is the answer because when something is left after something evaporates that shows the chemical change.

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%

the increase of protons   hope this

im pretty sure its b