How do the particies in a liquid create surface
tension?

It's been a while since I've taken Chemistry but here's what I know:

There are small, weak bonds that form between water molecules. These bonds make it so liquid molecules (water, in this example) cannot move as freely as a gas, but their bonds aren't nearly as strong as a solid. The bonds are formed when a hydrogen atom is attracted to an oxygen atom (because they have an opposite charge). This bond plus the gas molecules hitting the water causes surface tension.

(Let me know if this is wrong and I hope you have a lovely day!!)

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%

your answer would be “dry”