Question

question 2
metallic magnesium reacts with steam to produce magnesium hydroxide and hydrogen gas.
a. if 24.3 g mg are heated with 12.0 g h20, identify the limiting reactant - magnesium or water (steam)?

Answer 1

Explanation:

$molar \: mass(mg) = 24g. {mol}^{ - 1} mass = 24.3g \\ molar \: mass(h20) = 18g. {mol}^{ - 1} mass = 12g \\ n = \frac{mass}{molar \: mass} \\ n(mg) = 1.01mol wich \: is \: substance \: a\\ n(h2o) = 0.67mol \: which \: is \: substance \: b \\ \frac{ |n|a }{ |n|b } : \frac{a}{b} \\ \frac{1.01}{0.67}: \frac{1}{2} \\ 1.51 > 0.50 \\ therefore \: substnce \: b \: which \: is \: water \: steam \: is \: limiting \: reagent$