For each of the following, choose the measurement with the appropriate si prefix a 4.802 x 10-g 4.802 kg 4.802 ug 4.802 mg 4.802 ng b. 3.80 x 10-m 3.80 nm 3.80 km 3.80 cm 3.80 um c. 2.798 x 10-25 2.798 ps 2.798 cs 2.798 us 2.798 ds d. 8.8 x 10- 8.8 ng 8.8 pg 8.8 mg 8.8 kg

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%

answer: atomic mass was originally used to arrange elements on the periodic table, but is no longer used to organize the modern version.

explanation:

originally atomic mass was used to arrange elements on the periodic table from left to right in a row. each column then shows similar properties of elements of a group.

in modern periodic table, the atoms are arranged in increasing atomic number. as atomic number represents the number of protons in an atom which is unique for every atom.  

i believe it is c for plato

c is the correct answer on the lab