Help me Benjamin please

1...option B

2... peroids

3..group

4.. metals

5...7

6...dmitri mendeleev

7.. xenon

8... compound can be broken down by physical means

9... they can be broken down into simpler substance

sry if its wrong

last two 8th and 9th i do t think ots correct

1.) Atomic number

2.) Groups

3.) Period

4.) Metals

5.) 7

6.) Dmitri Mendeleev

7.) I think it's Chromium

I don't know the rest

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%