Question #c270e

1 Answer
Feb 26, 2017

The mass of Mg reacted was 15.08 g.

Explanation:

This is an example of the Law of Conservation of Mass.

The mass of the products must equal the mass of the reactants.

The chemical equation is

#"2Mg" color(white)(ll)+color(white)(ll) "O"_2 color(white)(ll)→ "2MgO"#
#color(white)(l)xcolor(white)(l) "g"color(white)(m)+ "9.92 g" = "25.00 g"#

#x = "25.00 - 9.92 = 15.08"#

∴ The mass of #"Mg"# reacted was 15.08 g.