Hey there!
MgCl₂
Find molar mass of magnesium chloride.
Mg: 1 x 24.305
Cl: 2 x 35.453
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95.211 grams
One mole of magnesium chloride has a mass of 95.211 grams.
We have 2.40 moles.
2.40 x 95.211 = 228.5
To 3 sig figs this is 229.
The mass of 2.40 moles of magnesium chloride is 229 grams.
Hope this helps!
