HELP How many grams are in 2.500 mol of magnesium hydroxide?

58.33 g
0.04286 g
145.8 g
100.8 g
23.33 g

145.8g

Explanation:

Given parameters:

Number of moles of magnesium hydroxide  = 2.5mol

Unknown:

Mass of Mg(OH)₂  = ?

Solution:

To solve this problem we use the expression below;

  Mass of Mg(OH)₂ = number of moles x molar mass

 Molar mass of Mg(OH)₂ = 24.3 + 2(16 + 1)  = 58.3g/mol

 Mass of Mg(OH)₂ = 2.5 x 58.3  = 145.8g

i believe the answer is three water molecules