What is the molar mass of PbCO4

283.21 g/mol

Explanation:

molar mass = mass of Pb + mass of C + mass of O times 4

M = 207.2 + 12.01 + 16.0(4)

= 219.21 + 64

= 283.21 g/mol

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%

level 4 to level 2 : ))