What mass does 4.41 moles of cobalt have? Help

260 g

Explanation:

Data obtained from the question include:

Mole of cobalt (Co) = 4.41 moles

Mass of cobalt (Co) =...?

The mole of a substance is related to its mass according to the following equation:

Mole = mass / Molar mass.

With the above formula, we can obtain the mass of 4.41 moles of cobalt as follow:

Mole of cobalt (Co) = 4.41 moles

Molar mass of cobalt = 59 g/mol

Mass of cobalt (Co) =...?

Mole = mass /Molar

4.41 = mass / 59

Cross multiply

Mass of cobalt = 4.41 × 59

Mass of cobalt = 260 g

Therefore, the mass of 4.41 moles of cobalt is 260 g

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%