How does the law of conservation of mass apply to this reaction: mg + hcl > h2 + mgcl2 ?

Explanation:

Law of conservation of mass:

According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.

Explanation:

This law was given by french chemist  Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.

Chemical equation:

Mg + HCl → H₂ + MgCl₂

24 g + 36.5 g = 2 g+ 95 g

60.5 g = 97 g

The reaction does not hold the law of conservation of mass, because it is not balanced.

Balanced chemical equation:

Mg + 2HCl → H₂ + MgCl₂

24 g + 73 g = 2 g+ 95 g

97 g = 97 g

this equation completely follow the law of conservation of mass.

hey there!

mass = 6.75 g

volume =   9 cm³

therefore:

d = mass / volume

d   = 6.75 / 9

d = 0.7 g/cm³

answer b