Question

According to the law of conservation of mass, how much mercury was present in the mercury (II) oxide? *

Answer 1

Mass of Mercury(Hg) : 55.8 g

Further explanation

Given

Reaction

2HgO ⇒ O₂ + 2Hg

Required

Mass of Mercury

Solution

Conservation of mass applies to a closed system, where the masses before and after the reaction are the same

So mass of reactants = mass of products

Mass of reactants = mass HgO = 60 g

Mass of products = mass O₂ + mass Hg

60 g = 4.2 g + mass Hg

mass Hg = 60 - 4.2

mass Hg = 55.8 g