The chemical formula for the compound magnesium perchlorate is Mg(ClO₄)₂
Magnesium perchlorate or Mg(ClO₄)₂ is an ionic compound.
Perchlorate here is an anion which is represented by ClO₄⁻. Perchlorate is a polyatiomic anion, where one Cl atom is bonded to four O atoms.
The magnesium cation is represented by Mg²⁺
So one Mg²⁺ cation combines with two ClO₄⁻ anion to form one molecule of Mg(ClO₄)₂
The volume of 1.00 lb of mercury metal : 33.352 ml
<h3>Further explanation </h3>
Density is a quantity derived from the mass and volume
Density is the ratio of mass per unit volume
Density formula:

ρ = density
m = mass
v = volume
Density of metal(mercury) = 13.6 g/ml
mass of mercury : 1 lb = 453,592 g
So the volume :

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