Mg(OH)2(s) + 2HCl(aq) −→ 2H2O(l`) + MgCl2(aq)
It Is early and I am too lazy to see which species is limiting so I will assume that magnesium hydroxide limits and drives this reaction.
6.27 g Mg(OH)2 (1 mole Mg(OH)2/58.326 g)(1 mole MgCl2/1 mole Mg(OH)2)(95.21 g/1 mole MgCl2)
= 10.2 grams MgCl2 produced
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