Question

In an experiment, 24g of magnesium react with 73g of hydrogen chloride to produce a gas and 95g of magnesium chloride.

Write a balanced chemical equation for this reaction
What type of chemical equation for this reaction?
Do these results support the Law of Conservation of Mass Explain your answer.

Answer 1

Mg + 2HCl=== Mg(Cl)2 + H2

The Reaction is a single displacement reaction.

Yes!

This reaction obeys the law of conservation which states that for a closed system... Matter and energy transfer is constant.

Meaning that the Mass of products must equal mass of Reactants

To prove this

lets Calculate the Mass of reactants

24g + 73g=97g.

Mass of Products...

95g + x.

let's calculate the mass of Hydrogen produced.

Note: You can get it using any of the reactants... I'll use Magnesium

Now from the balanced reaction.... 1mole of Mg reacts to produce 1mole of Hydrogen

Moles of Mg=Mass/Molar Mass

Given Mass=24g

Molar mass of Mg=24

Mole of Mg =24/24

=1mole

Since Mole ratio of Mg and H2 is 1:1.... Therefore 1Mole of Hydrogen is produced too.

To get Mass of H2

Again

Mole=Mass/Mm

Known= 1mole of H2 isproduced

Mass of H2 =2g

Mole=Mass/Mm

Mass =Mole x Mm

= 1 x 2

=2g

Now

Total Mass of products is

95 +2 = 97g.

This is the same with the Mass of Reactants

So The Law of Conservation of Mass Holds.